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					SUGGESTIONS ON SOME POINTS OF ANATOMICAL
   NOMENCLATURE. By P. H. PYE-SMITH, M.D., Lecturer
   on Physiology, Guy's Hospital.
                                 I.
IN asking the attention of anatomists to the modifications in
names proposed in the following pages, I fully admit the incon-
venience of any change in itself, and the mischief which ensues
when affectation of precision in language takes the place of
accurate knowledge of the objects of language. For the accom-
plished anatomist and physiologist names are scarcely of even
secondary importance. But for the learner it is otherwise; and
experience of the difficulties which ambiguous or misleading
names occasion to students has led me to note down, from time
to time during the last ten years, those points which I have
found most troublesome, and which may be improved with the
least amount of change.
   The most important characters which nomenclature in
anatomy, as in any other branch of science, ought to possess,
are clearness and convenience. Each object should have only a
single name in use, and each name should be sufficiently dis-
tinctive. The double nomenclature of Linnamus has proved no
doubt of great advantage to zoology and botany; but the objects
of human anatomy and physiology, whether normal or morbid,
the organs and the tissues, the vital processes and their results,
cannot be classified like plants and animals. For many of them
are not comparable; and if some, as for example cells,, admit of
a natural arrangement, they must be classified from several
points of view-as to size, shape, age, functions, and origin.
Hence the name should not fix too rigidly the position of the
object indicated in a system, but allow of its falling into its
place in each of the systems to which it belongs, by structure,
by chemical composition, by physiological function, or by the
history of its development in the individual or in the race.
   A name then should first, if possible, consist of a single word,
for the reason just given, as well as for the practical advantage
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.           155)
of brevity. Many anatomical terms, as foremen lacerum medium
basis cranii and iter a tertio ad quartum ventriculum cerebri,
are explanatory phrases, which become intolerable when quoted
habitually.
   Secondly, it should also be capable of forming an adjective.
This is an additional reason against a binominal nomenclature.
   In the third place, every name should have its Latin as
well as a vernacular equivalent. Beside euphony and flexi-
bility in forming adjectives and compounds, the community of
scientific interest among civilised nations makes this an indis-
pensable rule. It is scrupulously followed by zoologists and
botanists, with the best results, and its neglect by anatomists
is always inconvenient. -The recent advances in cerebral
anatomy made in France have failed to be as generally appre-
ciated as they deserve, in great part because of the arbitrary
descriptive phrases employed, and the absence of carefully
chosen Latin synonyms. German writers are less blame-
worthy in this respect, and the most fruitful terminologists,
as Virchow and Haeckel, are careful to give every new German
name its appropriate Latin equivalent.
   In England we no longer talk as Heberden and Baillie did, of
vesicles as "little bladders," and of the caecum as "the blind
gut." Even in their time, words like Paunchfleece, Huckle-
bone, and Snivel-gland were already obsolete. The older anato-
mists and physicians, Caius and Harvey, Willis, Sydenham, and
Mead, wrote in Latin; and when English came into use for
scientific works, there was a disposition to translate the familiar
Latin phrases into English equivalents. This was the more
natural, from the anatomical knowledge of laymen during the
seventeenth and eighteenth centuries being far greater than that
of the present day. But Douglas in 1732 set a good example by
retaining the Latin names only in his translation of Winslow's
Anatomy, and this practice was followed by Hunter and by
later writers.
   In anatomy, as in other sciences, we gain accuracy by the use
of technical terms, and English words are far better left to their
proper place in general literature. "Sinew," "gristle," " mid-
riff" are words as appropriate to colloquial and literary use as
are "tendon," " cartilage," and " diaphragm " to that of science.
 156                       DR PYE-SMITH.

    The German language, being less rich, less refined, and less
 fully developed than our own, still uses such terms as Herzbezctel,
 Wollwstrgane, Axencylinderfortsatz, but Latin forms are gradually
supplanting such barbarous words, as the Latin type is taking
the place of black letter in Germany.
    On the other hand, the genius of the French language forbids
 the use of foreign words which bave not been subdued into a
 Gallic form; while it allows a certain directness of speech which
 English and Americans would avoid. "Bulbe rachidienne "
 (like Tite-Live) is an example of the one tendency, "grand
fessier " of the other.
    While each nation must continue to use its own language in
accordance with its own laws and habit, it is obviously
desirable that there should be a common Latin nomenclature;
and it is well that English anatomists have almost universally
adopted it.
    Synonymms.-Many of these are very confusing, and should be
discarded when possible; but others, which are too deeply
rooted to be got rid of, should be carefully noted and explained.
Students would find their labours lightened if warned at once that
the same regions are denoted by cervix and collum, by crurcus
and femorals, brachiclis and humeralis, peronceus and fibularis,
ultna and cubitus, pillars and columns (of the external ring),
momentum and epiploon.
   On the other hand, one word sometimes does duty for several
things. Here, however, little practical inconvenience results.
There is not much risk of confusing the " testes " and " tonsils"
of the brain with their namesakes, or the biceps of the arm with
that of the thigh, or ventriculus, as applied to the stomach, with
those of the brain, or the heart. Still, when possible, it is better
to keep to the zoologists' and botanists' rule of each distinct
object hating a distinct name.
   Signiificance.-All scientific names were once, of course, signifi-
cant; and when the whole, or the most important part of the thing
signified can be expressed in its name, the advantage is obvious.
Sarcolemnna, for example, is an admirable word, short, distinc-
tive, and expressing the undoubted and important fact that the
object denoted forms the skin around what is already supposed
to be known-a striated muscular fibre. Chondroma again
        ON SOME POINTS OF ANATOMICAL NOMENCLATURE.           1 L-)7
denotes, by a well-understood convention, a morbid growth,
having the histological characters of cartilage. In both -these
cases it will be observed that the value of the term depends on
our being able to refer the new object to another already known.
But significant terms are often imperfect, or even misleading.
Supinator longus gives a very incomplete account of the action
of that muscle. The Glandula ptuitaria is not a gland, and
does not secrete phlegm. In the present insufficiency of our
knowledge, the best names are probably those which have no
meaning, and therefore cannot mislead. The first essential, after
all, in a name is distinction, and no one objects to personal
names having either lost all significance or being contradictory
of the qualities of the man who bears them. We may profit by
the experience of zoologists in this matter. Many good generic
words are meaningless, as Aphis and Antedon, while the
attempt to make others significant has led to such absurd results
as Parodoxurus and Distoma.
   Affixing the name of a person to an anatomical structure is a
common method of nomenclature. The objections to it are, first,
that it makes a double name; secondly, that it conveys a
meaning which is often historically incorrect-thus, Galvanism is
a title as unjust to Volta as America is to Columbus; and
thirdly, it becomes confusing when the lymph-follicles of the
spleen and the, acini of the uriniferous tubes are alike called
 Corpora Maipighiana.
    Etymological Correctness and Eutphony.-We cannot afford
to be very scrupulous on these points; and like zoologists
 and botanists, must allow a name, once given and gene-
rally recognised, to stand. We may sometimes venture to
vary a little when the change cannot lead to confusion, and
when the original or current form perpetuates a blunder in
spelling. Thus, cythode for " cytod " may be fairly accepted, in
the same way as we may write leuohamia, ancylosis, amphioxys,
and myriopoda, instead of the more common and erroneous forms
leukemia, anchylosis, amphioxus, and myriapoda. On the other
hand, albumin, as the name of a proximate principle, is a con-
venient variation of " albumen," the crude white of an egg. And
it would be undesirable to reject so convenient and generally
accepted a word as endot helium, because it was formed by His in
I P-8                      DR PYE-SMITH.
seeming ignorance of the original meaning of "epithelium," as used
by Ruysch and Astruc.
                               II.
   The chief modifications which seem desirable with regard to
the nomenclature of the SKELETON consist in applying to it the
general terms used in vertebrate morphology. The primary
division of the skeleton into its axial and appendicular parts,
 and the use of the terms dorsal and ventral, pr&e-axialand post-
axial, might be introduced with advantage into anatomical
text-books. The difficulty which arises from the more or less
prone or upright position of vertebrate animals, is increased in
the case of man, by the fact that the usual position in which the
human body is studied in anatomy and in medicine is neither
the one nor the other, but supine. The confusion which even
the best manual (Ellis's Anatomy) does not escape in the use of
the terms beneath, below, behind, above, would be prevented by
the introduction of the more general system for denoting relative
position; especially if careful use were made of such unam-
biguous phrases as " under cover of," " deeper than," " superficial
to." And in describing the limbs it would be far better to discard
the terms inner and outer altogether, and speak of structures
with reference to the radius or tibia and the ulna or fibula.
   The word dorsal being thus appropriated to denote the opposite
relation to ventral, it would be well to apply the term thoracic
to the vertebrae bearing ribs in human as well as in comparative
anatomy.
   Among the bones of the skull it would be better to write
palatal, turbinal, squamrosal, and petrosal (or periotic), instead of
the palate bone, the turbinated bone, the squamous and the
petrous portions of the temporal, both for uniformity and for the
convenience of a quasi-substantive over a more cumbrous
phrase. On the other hand, it would be well to extend the
word invented by Ingrassias for the stirrup-bone in man, to its
homologue in Sauropsida, so as to avoid confusion between the
stapes (" columella auris ") and the " columella " of the lizard's
skull. It is of less importance whether the cheek-bone retain
its name of " malar" among other animals, or be called jugal in
man; but so small a bone cannot want two names, and the
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.              159
 latter change would probably be the easier. There seems no
 reason why the term maxilla should not be restricted to the
 upper jaw-bone, and mandible used for the lower. There need
 be no corresponding change in the so-called " pterygo-maxillary"
 and " stylo-maxillary ligaments"; for the former should be
 described as a tendinous intersection between the buccinator
 and the superior constrictor, and the latter as a process of the
 deep cervical fascia.
    In the carpus no confusion could arise from calling the
os semilunare, the lunare, as usual abroad, and pyramidale might
be gradually introduced instead of " cuneiforme," so as to
distinguish this bone from those of the same tame in the foot,
best called ecto-, meso-, and ento- cuneiform. It would also be desir-
able to expunge the name scaphoid from the tarsus, and to call that
bone the naviculare, so as to avoid confusion, and prevent the
supposition that it is the homologue of the scaphoid in the hand.
    Some of the foramina of the skull might be easily lightened of
a weight of words. The foramina lacera basis cranii, anterius,
medium, and posterius have no natural connection. The first
should be always called " the sphenoidal fissure," a phrase which
expresses at once its shape and its boundaries, the last " the
jugular foramen;" while foramen lacerum, without addition,
fits very well the more irregular opening in the middle fossa.
I would also suggest that instead of "spheno-maxillary fossa,"
the cavity of that name should be known as Meckel's fossa.
This would associate it with the ganglion, which has nearly
dropped its synonym of "spheno-palatine," and would avoid
confusion with the spheno-maxillary, spheno-palatine, and
pterygo-maxillary openings into the fossa.
   The traditional nomenclature of LIGAMENTS and fasciae has
already been greatly simplified. Students are generally spared the
enumerationof the tendonof thequadriceps andof the synovial folds
named ligament alaria and lig. mucosum, among the ligaments of
the knee; and the processes of deep cervical fascia known as lig.
spheno-maxillare, lig. pterygo-maxillare, and lig. intermaxihlare are
fast losing their misleading names. Lig. arcuata, externa et internal
are unnecessary synonyms of certain parts of the lumbar fascia, and
" posterior layer of the triangular ligament " of part of the pelvic
fascia. The descriptive anatomy of the fasciae, however, so im-
 160                        DR PYE-SMITH.

  portant from a surgical point of view, has been greatly neglected,
 and needs rewriting. In the description of femoral hernia it is
 a pity that the septum crurale, "crural ring," and rural canal are
 not called " femoral."
    The human MuscnEs have names generally accepted, and
 though these might here and there be made more symmetrical
 and descriptive, the change would probably not be worth the in-
 convenience. Some names expressing doubtful or erroneous
 functions, as tensor palati and erector penis, are now generally
 discarded for their synonyms, circumflexus palati and ischio-
 cavernosus. An unfortunate attempt was made several years ago
 to alter the received meaning of the terms flexion an dextension
 as applied to the ankle-joint, but at present I believe all writers
 agree in calling the foot " flexed " when it is bent up, and " ex-
 tended" when it is stretched out. In description, the adductor
 pollicis should be counted as one of the palmar interossci. This
 agrees with its action and nervous supply, and makes the dorsal
 and palmar interossei equal in number.
    The muscles of the back have always been a puzzle to
students, as much from the intricacy of the nomenclature and
arrangement of text-books as from their natural complexity. In
the last edition of Quain a much better arrangement is adopted,
and I would only suggest that the splenius and complexus are
best put together as the two great crossing supports of the head
 (erector capitis).
    It would perhaps be worth while to keep the word "cervix
for the back of the neck (transversalis cervicis, semispinalis
cervicis), and " collum " for the rest (longus colli).
    The arrangement would then run thus:
Trapezius and Latissimus Dorsi. Rhomboidei and Levator
    Anguli Scapulae.
Serrati postici and vertebral fascia, including posterior layer of
    lumbar fascia.
Splenius (omitting S. capitis, S. colli) and Complexus (omitting
   Biventer cervicis).
Erector spine: one muscle dividing into three prolongations,
   viz., external-sacro-lumbar, dorsal, and cervical parts (sacro-
   lumbalis, M; accessories, cervicalis ascendens); middle-dorsal,
   cervical, and cranial parts (longissimus dorsi, transversalis cer-
   vicis, trachelo-mnastoid) ; internal-(spinalis dorsi).
        ON SOME POINTS OF ANATOMICAL NOMENCLATURE.             161
Transverso-spinales, including semispinales (dorsal and cervical),
   multifidus spine, and rotatores spine.
Supra and inter-spinales, inter-transversales.
Recti et obliqui capitis.
    In the nomenclature of ARTERIES, I would recommend the
definite admission of a thoracic axis with a humeral, acromial,
and pectoral branch. The " acromial thoracic' artery is most
frequently a short trunk dividing into three branches, like the
thyroid and coeliac axes; and it has been already described as an
axis. The little Anastomotica of the brachial might be relieved
of its qualification " magna."
    Might the branches of the femoral known as " superficial ex-
 ternal pudic" and "deep external pudic" be called superficial
 and deep pubic Their distribution would then be better indi-
 cated, their position internal to the axis of the limb would
 not be obscured, and the " internal pudic " artery, with which
 they have no natural alliance, would assume its proper position
 as the only pudic artery.
    The names of NERVES, like those of arteries, are generally
distinctive and well known. I would, however, recommend
lightening the greater, lesser, and external petrosal nerves of
 such additions as make of the first a nervus petrosus superficialis
 major; the general adoption of the term radio-spiral for musculo-
 spiral nerve, as more descriptive of its distribution; and the
 omission of the unnecessary and misleading adjectives " superior "
 and " inferior," applied to the gluteal and pudendal nerves re-
 spectively. The ilio-inguinal nerve ought certainly to be called
 the inguinal simply, for it has no branch corresponding to the
 iliac branch of the ilio-hypogastric.
    The traditional names of the cranial nerves are so firmly
 established that it is scarcely possible to make any important
 changes. Even Sbmmering's numeration has never supplanted
 in this country the less convenient one of Willis, who evidently
    caAd them, neither on the brain nor by the foramina of the
 skull, but by those in the fresh dura mater. Perhaps the best
 plan is to omit the numerical terms altogetherand use the names-
  Olfactory (meaning the numerous grey nerves which pass through
     the cribriform plate to the olfactory bulb).
  Optic, including the optic tract.
   VOL. XII.                                               L
 162                            DR PYE-SMITH.
 Oculo-Motor, trochlearis and abducent.
 Trifacial, with its ophthalmic, maxillary, and mandibular divisions.
 Motor Facial (Portio dura).
Auditory.
Glossopharyngeal.
Vagus and Accessorius.
 Hypoglossal.
    The nomenclature of the BRAIN stands more in need of
 revision than that of any other part. Most of the fanciful terms
imposed by the early anatomists have happily fallen into disuse,
but a uniform terminology of the convolutions still awaits
completion. The question whether the fissure of Rolando or
the ascending branch of the Sylvian fissure should be accepted
as the boundary between the frontal and parietal lobes, is
now practically decided for the former, in spite of the authority
of Gratiolet and Bischoff and Huxley.' The term ".optic thala-
mus " is a misleading and cumbrous abbreviation of the proper
name thalamus nervorum opticorum, and the name thalamnus,
without qualification, is at once distinctive, convenient, and free
from a false suggestion as to the function of the part. The
corpora albicantia sive mammillaria and the taenia hippocampi
should be described as parts of the fornix, not as independent
structures. Of all the synonyms of the Hippocampus minor
(Ergot of Moraud, eminentia unciformis, colliculus, unguis, calcar
avis), the last is the most distinctive, and brings it at once into
relation with the calcarine fissure. The Hippocampus major
may then drop the adjective, as well as its synonym of corn
ammonia. The pineal body and pituitary bodies are more con-
veniently called conariurm, and hypophysis. The French term
Bulb is, for shortness, distinction, and accuracy, far preferable
to the cumbersome " medulla oblongata." The phrase bulbar
paralysis, which is now familiar iil medicine, will facilitate this
change.
   Kolliker and Virchow showed long ago that the anatomy of
  I The Fissure of Rolando and the Insusl are far more distinctive names than
any proposed to replace them; and ascending frontal and parietal gyri are better
so named than central (Huschke and Ecker), or antero- and postero-parietal
(Huxley). Besides Professsor Turner's well-known paper in the Efdin. Med.
Journal (1866), and Mr Galton's admirable edition of Ecker's work, the last
edition of Quain's Anatomy hm good figures of the convolutions.
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.              163
the Arachnoid in the skull is not that of a serous membrane,
and it is much better described as forming part of the dura
mater and pia mater. Although in the cord there is a true
" parietal arachnoid," the development of the membrane, as
well as its pathology, forbid us to class it with the great
lymph-sac of the pleuro-peritoneal cavity, and its offsets, the
pericardium and tunica vaginalis. The term cerebral arachnitis
might also well be dropped, the common inflammation of the
pia mater being described as meningitis, and the rare inflamma-
tion of the dura mater as pachymeningitis.
   The aqueduct of Sylvius, or simply the aqueduct, is a better
name than the. cumbrous description " iter a quarto ad tertium
ventriculum cerebri."
   The word Pons (Varolii) might well be restricted to the
great transverse commissure of the cerebellum, excluding the
ascending fibres between the bulb and the crura which it
bridges over, or the deeper grey matter of the mesencephalon,
but including as its lateral crura the so-called processes e cerebella
ad pontem, a misleading term which is best forgotten. The
processes e cerebello ad medullam and pr. e cerebello ad testes
would then be known as the superior and inferior peduncles of
the cerebellum.
   The corpora quadrigemina should bear as a synonym the
more general and instructive term " optic lobes," and drop the
 meaningless synonyms of nates and testes.
    The olfactory peduncle or commissure, and the olfactory lobe,
 are at length nearly rid of the misleading name of nerve.
   The word Cerebrum ought to be strictly limited to the
Hemispheres with the Corpus callosum and Fornix. The
Corpora striata and the Thalami belong to the spinal system,
and we have the word- Encephalon when we wish to denote all
that is contained in the skull.
   The terms nucleus caudatus and nucleus lenticularis are not
 well chosen, but they are so generally adopted, especially by
 French anatomists and pathologists, that we must continue to
 use them. The phrase capsule interne for the white substance
 between them, which Vieussens called " double centre demicir-
 culaire," may be accepted as an improvement.
    There is not much to alter in the description generally given
164                        DR PYE-SMITHf.
of the EYE. The three " himours " are now rarely mentioned,
for the gelatinous connective tissue of the vitreous is as different
from the aqueous humour as is the solid lens. The erroneous
account of a "posterior chamber" given in the older text-books
is also generally dropt. In the retina the so-called inner and
outer granule-layer is better called nuclear, as in the last edition
of Quain's Anatomy, than granular, which might have been
more suitably applied to the " molecular" layer.
   The anatomy of the internal EAR has been made needlessly
difficult by accumulation of names. As in so many other cases,
the Latin phrases, which when first applied were merely
descriptive, have acquired an unlucky precision by repetition.
Many of these terms may, however, be quietly dropped. The
most difficult part in the nomenclature of the ear is that of the
cochlea. The modiol-s, the helicotrema, the lamina spirals, the
fenestra rotunda, scala tympani, and scala vestibuli are all
excellent names. We need more precise terms for the opening
of the scala vestibule into the vestibule (apertura scake vestibuli),
and for the opening of the membranous cochlea into the sacculus
(canalis reuniens of Hensen): perhaps " osseous aperture " and
"membranous aperture" of the cochlea might serve. But the
great confusion is in the membranous cochlea. The term scala
media was originally applied to the spiral passage of a triangular
prismatic shape, which runs parallel to, between, and outside of,
the two other scale, bounded by the wall of the cochlea out-
side, the membrane of Reissner above, and the " basilar "
membrane, or lamina spiralis mernmbranacea below. It runs a
course between the other two. winding staircases, and no
better name than scala media could be devised. But it is now
frequently called canalis cochlearis (Cruveilhier, Hermann); by
others (Waldeyer) Ductus cochlearis (Schneckengang); while
canalis cochlea (Schneckencanal) is applied to the entire bony
cavity of the cochlea, including the three scale (Waldeyer,
Cruveilhier); and canal of the cochlea, canals membranaceus and
ductus cochleare are used as synonyms by other writers. Special
names have also been applied to the part of the scala media
which underlies the membrane tectoria, and even to the hollow
under the gable formed by the internal and external rods of
Corti. These ambiguous terms may all well be discarded, or
          ON SOME POINTS OF ANATOMICAL NOMENCLATURE.    165
cochlear duct or canal be used indiscriminately as synonyms
of the membranous cochlea, the scala media.
                                   III.
    The HISTOLOGiCAL terms in general use are almost all modern,
and few are so firmly rooted that they cannot be modified, if
necessary.
    The word CELL carries with it, in the history of its succes-
sive significations, an epitome of the progress of the last forty
years. It has lost its original meaning of a visible hole or cavity,
like the " cells" of a prison or of a honeycomb, though the old-
fashioned terms " cellular" (for areolar) tissue and " air-cells "
(for air vesicles) may still be met with, anl, surgeons have not
yet abandoned the hybrid and useless term " cellulitis." And we
have long learned to discard the meaning attached to the word
by Schleiden and by Schwann-a vesicle with cell-wall, nucleus,
and fluid contents; and may now define a cell as " a minute
living mass of nucleated protoplasm." It must be minute; for
if the organism grows too large, it divides and forms two cells.
It must be nucleated, that is, it either possesses, or has
possessed, a sharply-outlined refractive kernel, which resists
acetic acid, and is deeply stained by colouring matter. Schlei-
den's term, " cytoblast," is a useless synonym of nucleus, less
distinctive, longer, and involving a theory. For young cells
 without a nucleus, the word cythode, introduced by Haeckel,
is a convenient word; but there is no reason why we should
 follow him in misspelling it cytode, if it is a compound of
KVrTOq and 0&o-. Formed in.the same way, on the model of
cathode and anode, was Dujardin's term, Sarcode,l first applied
by him to the clear viscid fluid which exudes from the bodies
of helminths and many other minute worms under the cover-
glass, and extended by Milne-Edwards to what we now call
the protoplasm of foraminifera. Protoplasm was a word used
first, I believe, by Reichert, introduced into botany by Von
Mohl, and applied in its present sense by Max Schultze. It
 may be sufficiently defined as (1) morphologically, structureless;
 (2) physically, colloid: (3) chemically, protein; (4) function-
 ally, living, i.e., capable of growth, reproduction, and movement.
   So Milne-Edwards, but Little and Robin give aapKJ48J7S as the derivation.
 166                       DR PYE-SMITH.
  The nucleus of a cell, a sarcous element, a red blood disk, an
 axis-cylinder, an elastic fibre, are not made of protoplasm,
 because they are differentiated.
    The word corpuscle is convenient, if we keep it to its original
 vague sense of a minute solid body, thus including cells, but
 not confined to them. Red and white (or colourless) blood-
 corpuscles are therefore -perfectly correct names. though it is
 much more convenient to speak of them as blood-disks and leuco-
 cytes respectively. The latter term includes, of course, the
 similar colourless cells of lymph and pus. " Blood globules," a
 word still much used by French writers, should be entirely
 abandoned; nor is there any advantage in replacing the univer-
 sally recognised term cell (zelle, cellule, cellula) by globule, as
 Russ and other French teachers are doing. Dr Benjamin Guy's,
 term, liquor sanguinis, nearly answers to the German " plasma ;"
 but it is better to keep the former for the actual coagulable
 fluid of blood deprived of its corpuscles, and to use plasma as a
 more general term, including liquor sanguinis, liquor lymphae,
 liquor purns, the coagulable lymph of Hunter, in fact, all the
 fluids, apart from their solid elements, which are capable of
 forming fibrin or myosin.
    The perplexing nomenclature of the colouring matter of the
'blood seems to have gradually settled into something generally
intelligible. Berzelius's " hbmatosine," which he never saw
 crystallized, is almost forgotten. Hcemoglobin is better, because
 shorter, than. Hoematoglobuline and Hmatocrystalline. Haema-
 tin of Hoppe-Seyler, haxmatoidin of Virchow, hbmin of Teich-
 mann, and metlhemoglobin (chlorhbematin) of, Mulder, remain to
 denote products of hemoglobin, and have now their respective
 meanings definitely fixed. Prof. Stokes's word, cruorin, seems
to be almost unnecessary as a synonym. Oxybeemoglobin and
reduced hemoglobin and acid-hbmatin are names that explain
themselves, and the latter is certainly more convenient than the
"chcbmatoin " of Preyer. It is a pity that the word " hoema-
tein" has been applied to a product of logwood.
    The nomenclature of EPITHELIUM is a difficult point. In the
first place, I would call attention to the fact that the ordinary
classification of epithelia, like so many others, compares things
which are not comparable. It is absurd to divide epithelium
          ON SOME POINTS OF ANATOMICAL NOMENCLATURE.                         167
into columnar, squamous, pigmentary, and ciliated; for a cell may
contain pigment, whatever its shape, and may bear cilia, what-
ever its contents. The varieties of epithelium must be classified
under several heads: the size and shape of the constituent cells;
their possession of a nucleus, of cilia, or other appendages; the
nature of their contents and their chemical composition; the
arrangement of the cells in one or more layers; their origin from
certain embryonic structures; and the functions they subserve.
The terms conical, spheroidal, hexagonal, columnar, goblet-
shaped, &c., should be used as strictly descriptive of the shape
of the cells, and nothing more. Secreting epithelium is not
always spheroidal, nor ciliated always cylindrical.
   Ts it desirable to make a division of the Epithelia into three
forms, denoted by the terms epidermis, epithelium proper, and
endothelium? The first is the oldest word, and will certainly
continue to be used for the epithelial layer of the external skin.
Epithelia, or epithelis,' was first applied by Ruysch to the mem-
brane which covers the papillae of the mouth, and by Astruc,
with a different etymology, to "La peau fine et delicate qui
recouvre le mamelon." The third term endothelium was intro-
duced by His, and has been very generally adopted. Lately,
some English histologists have objected to it, and the question
was debated in the Quarterly Journal of Microscopical Science for
1874 (pp. 219, 391) by Drs Michael Foster and Cavafy. It seems
to me that the latter writer had the best of the argument. He
disposed of the etymological difficulty by explaining endothelium
as a contraction of endo-epithelium; and " epithelium " itself is, as
we have seen, by no means so pure or so appropriate a formation
that it can look down on its younger brother. A much more
important objection is that all the structures which His called
epithelium do not, as he supposed, come from the inner layer of
the embryo. And this Dr Cavafy has not, I think, fully met; for
increasing knowledge has rendered it improbable that the
genito-urinary epithelium comes from anything but mnesoblast,
  I In the Quart. Journal of Aficr. Sc., xiv. p. 220, " epithelida" is given as
the original form, but this, as Dr Cavafy points out (ibid. p. 392), is merely the
accusative of "epithelis "-integumentum illud supradictum potius. epithelida
dixero vel integumentum papillare ,prolabioruln. Epithelia was the alternative
form used by Ruyseh, epithslion by Astruc.
 168                        DR PYE-SMITH.

and yet it is hopeless to think we can induce people to call the
epithelium of the ureter endothelium.
   But is this, after all, conclusive against the use of "endo-
thelium" ? Did we ever succeed in making our students call
the epithelium of the mouth, or that of the central canal of the
cord, epidermis? And yet both have sprung from the epiblast.
Because we cannot draw lines more precisely than nature has
drawn them, must we give up classification altogether ? We
meet with gradations everywhere, but we must not refuse to
define species because the limits towards genus and variety are
often arbitrary.
   "Alle Gestalten sind hhnlich, doch keine gleichet der A-ndern,
     Und so deutet der Chor auf eim geheimes Gesetz"
    The only natural classification of natural objects is by type,
 describing the most differentiated forms, and grouping others
around them so as to show their genetic relations. And from
this point of view there is surely no difficulty and great practical
advantage in recognising three types of epithelia, which may
still be called epidermis, epithelium, and endothelium.
   I would propose therefore that, still keeping " epithelium " as
a general name for any cells laid close together, so as to form
one or more layers upon a free surface, we should, when we wish
to indicate precisely (so far as we know) the embryonic source
of epithelia, use the terms epiderm, mesoderm, and hypoderm,
corresponding to epiblast, mesoblast, and hypoblast. The epi-
thelia of the adult body might still be arranged under three
primary heads, which would include the several local varieties,
bronchial, intestinal, vesical, &c., and might be defined as fol-
lows:
   (1.) Epidermis: epithelium covering the outer surface of the
body; in several layers, the uppermost corIneous; derived from
the epiblast; with sebaceous glands opening on to it; and
affected by characteristic lesions, as psoriasis and epithelial
cancer.
  This would include all that is commonly known as epidermis,
but would exclude the epithelium of the mouth, rectum, and
urethra, and that of the sebaceous glands and mamma.
   (2.) Epithelium, in the restricted sense of the word: covering
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.             169
 the internal surfaces which communicate with the exterior; in
 one or more layers; derived from the hypoblast; with muciparous
 glands opening on to it; and affected with characteristic lesions,
 as catarrhal inflammation and scirrhous cancer.
    This would include all the epithelium of mucous surfaces and
 of glands, whether derived from the epiblast like that of the
 mouth, or the mesoblast like that of the mamma and of the
genito-urinary tract.
   (3.) Endothelium: epithelium lining closed cavities; almost al-
ways in a single layer; the cells closely united by cement; rarely
bearing cilia; never secreting; derived from the mesoblast, and
prone to characteristic plastic (croupous or adhesive) inflamma-
tion.
   This definition would include Athe epitheliumn of the pleuro-
peritoneal cavity, of the lymph and blood-vessels, the " arachnoid,"
the uvea and pigment layer of the retina, the epithelium of the
air-vesicles and of the Malpighian bodies of the kidney, of syno-
vial membranes, bursae and ganglia, and of the scale, of the
vestibule and tympanum.
   In teaching we should point out that epidermis and epi-
thelium are more closely allied to each other than either of them
is to endothelium, which, on the other hand, forms a natural
link between the epithelia and the great group of connective
tissues.
   The epithelium of the mouth is epidermic in its origin: the
inside of a rabbit's cheek has a patch of fur upon it, and surgeons
speak of psoriasis of the tongue. Even the epithelium of the
esophagus is more like that of the mouth than is the gastric
epithelium, in the size and shape of the cells and in their morbid
conditions. When the skin is denuded of its horny cuticle, the
subjacent Malpighian layer of epidermis (well-named rete mu-
cosun) takes on much of the aspect and the life of a mucous
membrane, as we see after a blister has been applied to the
sin.
   On the other hand, the endothelial cells of a lymph space
approach very nearly the epithelioid connective tissue corpuscles
of a tendon.
   That such a classification would leave some " epithelia," with-
out further distinction is, I submit, in its, favour.
170                       DR PYE-SMITH.
    That which lines the central canal of the cord and brain, as
well as the epithelium of the membranous labyrinth, is epi-
dermic in origin, epithelial in possessing cilia and being bathed
in fluid, and endothelial in not communicating with the exterior.
The rods and cones, the cells of Deiters and rods of Corti, the
olfactory cells, and those lining the taste-goblets, are all ulti-
mately derived from the epiblast, but their differentiation has
gone much too far for them to be classed with epidermis, and we
can only speak of them as modified epitheliuni.
    In describing the skin it is well to utilise the two words
"epidermis " and "cuticle " by restricting the latter to the super-
ficial horny (not "corneous ") layer (Hornschicht), for which we
want a term. Moreover, this is the true vernacular meaning of
" cuticle" or scarfskin; for an injury never detaches the whole
of the epidermis without also involving the papillary layer of
 cutis: the cuticle which is separated by a blister is the horny
layer alone.
    In the same way, corium, which is useless as a synonym for
derm, or cutis vera, may well be utilised by being extended to
the corresponding vascular layer of mucous membranes. At all
events, I hope we shall not adopt the German plan of calling
this structure mucosa, a word which obviously belongs to the
whole internal skin. Mucosa (sc. membrane) consists of epi-
thelium and corium, just as the skin consists of epidermis and
derm.
    The terms used in describing MUSCULAR TIsSUE, so far as all
 histologists are agreed as to its structure, are convenient and
 generally accepted. There is no object in replacing Bowman's
 original name Sarcolemma by myolemma. The term " primitive
 bundle," as used by Kolliker and some other writers instead of
 muscular fibre, is inconvenient, if not incorrect. Even if the
 fibrillae are the true muscular elements, and not due as much as
 the disks to accidental arrangement of smaller particles, there is
 no impropriety in a fibre consisting of fibrille. Moreover, a
 "primitive fasciculus" enclosed in sarcolemma is totally dif-
 ferent from the mere bundles of fibres also called fasciculi, and
 bound together by perimysium.
     It is a pity that Schwann did not devise short and convenient
 names for the components of NERVE-FIBRES which he so accurately
           ON SOME POINTS OF ANATOMICAL NOMENCLATURE.                     171
analysed nearly forty years ago. His primitive sheath is now
called by many writers (e.g., Hermann, Budge, and Turner)
neurilemma, and though this has not been adopted in the last
edition of Quain's Anatomy, it is surely an excellent innovation.
There is no need for the word in its old signification of the
fibrous sheath of a nerve trunk. The fibrous sheath, or the
external perineurium are terms sufficiently clear, and if we wish
to refine further, we may distinguish the perineurium (a word
which ought obviously to include all the connective tissue of a
nerve) as external perineurium (fibrous sheath and its trabeculas),
funicular sheath of Ranvier (perineurium in the restricted sense
of Robin), and internal perineurium (intrafunicular connective
tissue).'
   The nomenclature of muscle and of nerve would then be sym-
metrical, and free from ambiguity. A muscle (or nerve) is
covered by a fibrous sheath(fascia propria, exoneurium), which
sends in trabeculae, dividing it into fasciculi (or funiculi), en-
closed in more or less distinct sheathes (perineurium, of Ranvier),
and the ultimate elements (fibres) are surrounded by delicate
vascular connective tissue (perimysiurn, perineurium, or endo-
neurium). The fibre in both cases possesses an elastic structure-
less primitive sheath (sarcolemma, neurilemma).
   The " medullary sheath of Schwann " is better called simply
myelin, to distinguish it from the primitive sheath or neurilemma,
and to avoid the abuse of the word medulla (Markscheide), which
ought to be confined to the marrow of bones, and set free from
its application to nerve-fibres, cord (medulla spinalis), and bulb
(medulla oblongata). Lastly, there seems no reason why we
should not drop one-half of Schwann's double name, and speak
of the axis instead of the " axis-cylinder " of a nerve.
                                IV.
   It would be be very desirable if the words GLAND, glandular,
adenoma, and other derivatives of glans and a48v could be
strictly confined to secreting organs. Originally, of course, any
round and smooth body was a gland, and the glans penis and
conglobate glands had a better claim to the name than the
   1 Perineurium (neurilemma) externum, internum and intimum of Funke
anil others. Epineurium, perineurium, and endoneuriurn of Axel Key and Retzius.
172                        DR PYE- SMITH.

pancreas or the peptic tubules. But the word is now irrevocably
connected with secretion, and our object should be to keep it to
that signification. Unluckily, it is still applied not only to the
true (secreting) glands, but also to lymph-glands and to so-called
"ductless glands.
   For the first set of organs we are sadly in want of a distinctive
name. The only word in use beside "gland" is the French
" ganglion lymphatique," which is scarcely better.
   Until a writer with the authority of Linnaeus, or of Virchow,
will impose a form like " lympharia " or some better title on these
organs, we must be content to call them lymph-glands, and to
disconnect them in description as widely as possible from the
true glands. It would once have been possible to use the Greek
word for the conglobate, leaving the Latin for the conglomerate
glands; but dnv, with its derivatives,adenocele, adenoid, adenoma,
is now applied as much to secreting as to lymphatic organs, so
that Trousseau's pathological name " Adenie " (multiple lympho-
mata, Hodgkin's disease) only serves to increase the confusion, and
with "adenoid" and "lymphadenoma" may perhaps best be
forgotten. "Lymphatic" will then be the adjective of lymph-
gland, as "glandular" is of (secreting) gland; the word adenoid
will be supplanted by cytogenic, and Iymphadenoma of Ranvier
by lymphoma of Virchow. Cytogenic tissue, defined as " retiform
connective with its meshes filled with leucocytes," is a term open
to the objection of implying a theory which is not yet universally
accepted, but it is distinctive and generally recognized.
   There is one change in nomenclature which would do some-
thing to bring accuracy into the description of these lymphatic
organs. Follicle is a somewhat meaningless word, applied indis-
criminately to an ovisac, a secreting crypt of Lieberkiihn, a
sebaceous gland, and a circumscribed mass of cytogenic tissue.
It would surely be an unmixed advantage to restrict its use to
the last signification, for the word is unnecessary in any other, and
is greatly wanted in this. It is now difficult to make students
(and others than students) understand that the " solitary glands"
of the intestine, the " closed follicles " of the root of the tongue,
the " lenticular glands " of the stomach, the " Malpighian
corpuscles " of the spleen, and the " acini " of the thymus, are
all exactly the same organs; that the tonsils and the " agminated
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.             173
glands" of Peyer are only patches of the same; that they
 are all closely connected in anatomy and in function (both
healthy and morbid) with the ampullae of lymph-glands, and
 that they are totally and absolutely unconnected with the acini
 of secreting glands. The word follicle, already applied to some
 of these structures, might easily be extended to all, and restricted
to them alone. A follicle would then be defined as " a circum-
scribed mass of cytogenic tissue."
   The correlative word acinus has fortunately not been so
wasted. It is seldom or never used of anything but a secreting
gland; and I would suggest that it ought not even to be applied,
as it sometimes is, to a lobule of the liver. Defined as " the blind
extremity of a secreting duct," it obviously applies to the
glomerulus of a sweat-gland, the ultimate lobule of the pancreas,
and the Malpighian capsule of the kidney, but it cannot apply
to the ultimate hepatic lobule, which has a secreting structure
of a totally different kind.
   Besides secreting or true glands, and lymph-glands, there
remain a miscellaneous set of organs, to which the same term is
still more or less vaguely applied-the pituitary body or hypo-
physis cerebri,the pineal bodyorconarium, the supra-renal capsules,
the thyroid, the prostate, the thymus, the spleen, the ovary.
    The confusion is unnecessary, for each of these organs has a
 name of its own, well recognised and generally used. The
 ovary of the higher vertebrates is not a gland, anatomically or
 physiologically; the spleen and thymus are cytogenic organs;
 the prostate is a mass of smooth muscle, thickset with muci-
 parous glands; the hypophysis does not secrete pituita, nor the
atrabilious capsules black bile.
    The term " ductless gland," which connects together such
dissimilar structures, simply means a gland which does not
secrete; according to the modern meaning of the word, a con-
tradiction in terms. A kidney turned iDto a multilocular serous
 cyst by obstruction of its ureter is really a "ductless gland."
 The practical mischief is that, since some of the heterogeneous
 crowd are now known to belong to the lymphatic system, the
 same is often assumed of the others.
    The term "blood gland" is no less misleading. The cyto-
 genic orgaus, no doubt, manufacture leucocytes, but the process
174                               DR PYE-SMITH.
is not one of secretion (vacuolation of involuted spheroidal
epitheliutm), and leucocytes are not the whole of the blood.
There is not the shadow of ground for the suspicion that the
" ductless glands," which do not consist of lymph-follicles, have
anything more to do with the blood than any other vascular
organ. It is just as likely that the supra-renal body makes black
bile, that the hypophysis secretes phlegm, or that the conarium
lodges the- soul. What are the functions of these four organs
we are entirely ignorant; but we are not ignorant of this, that
they have no sort of connection either with glands or with the
lymphatic system, and that they have no special connection
with each other. The thyroid looks like what one might
imagine a disused pancreas or lung would become if it under-
went colloid degeneration. The supra-renal capsule in its
deeper part bears some resemblance to ganglionic tissue, and in
its cortical, to a piece of a tubular gland or a lobule of a liver,
which has become obsolete and infiltrated with oil drops and
pigment.
   The supra-renal capsules certainly stand in need of a less
cumbrous name. The word capsula perpetuates the early mistake
that they are hollow, and a practical inconvenience arises in the
deadhouse from the same word being used for the closely ad-
jacent fibrous capsule of the kidney. I would therefore suggest
that the term used by Professor Owen in his Comparative Ana-
tomy-ADRENALs-might be generally adopted with advantage.
This convenient translation of the German Nebennieren is short,
and only expresses an undoubted anatomical fact.2
   In the description of the KIDNEY by most anatomists the
pyramids of Malpighi are spoken of as belonging only to the
medullary part of the gland. But, looking to its development,
and to its lobulated condition in other animals, and occasionally
in man, it is certainly more correct to describe the pyramids as
reaching to the surface, and composing the cortex by their con-
   1 Some observations of Dr Creighton, not yet published, promise to throw fresh
light on the obscure homology of the Adrenals.
  2 Critics will no doubt object to using an adjective as a substantive, but how
far this is admissible is entirely a matter of usage, quem penes arbitrum est et juset
norma loquendi. We speak of particulars, goods, blacks, yellows, blues, violets,
canonicals, decretals, regimentals, animals, herbals, and even of vitals and genitals,
and why should w e object to adrenals?
         ON SOME POINTS OF ANATOMICAL NOMENCLATURE.            175
joined bases. If the adrenals be no longer called capsules, that
 word would apply exclusively to the fibrous tunic of the kidney,
 and similar structures, as the tunica albuginea of the testis. The
 corresponding tunica propria of the LIVER may fairly be called
" Glisson's capsule," and the interlobular septa should then be
described as processes continuous with Glisson's capsule. In the
pig, they form real capsules or investments to each lobule, but in
the human liver this is not the case. The word " portal canal " is
an unnecessary and misleading synonym of these interlobular
septa or trabeculke. Scanty as the perivascular connective tissue
here is, it is strictly analogous to that which accompanies the
blood-vessels of the pia mater in the cord, to the tunica vasculosa
in the testis, and to the interlobular tissue of the pancreas and
other racpmose glands; and the object of nomenclature is to make
plain natural conformities of structure, no less than to dis-
tinguish things which differ.
   In describing the minute anatomy of the liver we cannot do
better than follow Kiernan's nomenclature of interlobular
branches of portal vein and of hepatic artery and duct, but the
term intralobular capillaries ought clearly to apply no less to
the centripetal and transverse connecting branches of the portal
vein than to the collecting branch which carries their blood from
the centre of the lobule to the sublobular vein outside. Both are
intralobular, but for convenience we call the vessels portal as
far as the centre, and hepatic beyond.

				
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