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The principles of classification of Ehynchophora, and their
division into families will be discussed in a subsequent memoir.
It is, however, proper to observe that the peculiar constraction
of prothorax above described as characteristic of the Ehyncho-
phora, is not exhibited in the Bruchidse, which family, as ob-
served by Lacordaire (Gen. Col. vii, 600), should be viewed as
closely related to, if not actually a portion of, the great family
Chrysomelidfid.



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44 B. G. Wilder on the Morphological



Abt. v.— On (he Morphological value and relations of the Human
Hand; by Bubt G. Wildbb, S.B., M.D.

[Abstract of a paper read before the National Academy of Sciences, Aug. 8, 1866.]

The morphological relations of the haman hand are of three
kinds.

1st, Its ipecial homology with the terminal segment of th^ an-
terior extremity in other vertebrates.

2d, Its general homology as a part of the skeleton ; which can
be fully enunciated only after a decision as to the morpholo^cal
relations of the scapular arch of which it is an appenoage.

3d, Its polar fiomologies with the corresponding parts on the
opposite side and at the opposite end of the Dody. Tnat with the
otner hand is universally regarded as one of symmetry or antago-
nism ; that with the foot is generally called its serial homology,
snd the point under consideration is whether this is merely a
serial relation and not rather one of antagonism, so as to consti-
tute a second kind of polar homology.

The course' of the argument is indicated by the following
propositions.

1. The extreme diversity and confliction of opinion* as to
the morphological relations of the human hand are chiefly due
to an over-estimate of its morphological valtie.

2. This misappreciation or the morphological value of the
hand is due to a non-recognition of the distinctions between the
two principles, morphology and teleoloCT.

8. Morpnology is the law of internal fcrm, of plan, of essen-
tial structure. Teleology is the law of special function which
determines size, shape and general appearance.

4. Homology is morphological identity ; analogy is teleolog-
ical resemblance; and neither relation necessarily implies the
other.

6. Morphology treats of unity of type; teleology treats of
adaptation to ends.

6. Morphology alone would be law without liberty, which is
despotism ; teleology alone would be liberty without law, which
is anarchy.

7. Morphology is conservative and tends toward centraliza-
tion ; teleology is radical and tends toward diflFusion.

8. The two principles may be traced in all structures, but the
one is often more prominent than the other.

9. With certain important qualifications it mav be said that
the clearest mani&statioi^s of morphology are to be observed in

* Some idea ef tble diTerrity of opinion may be sained by reference to Dr.
Oleland'e brief statement of the Tiewe of Tarious antnors in the 7 tb edition of
Qaain*s Anatomy, pp. 116-117, 1866, and to ihe remarln of Mirart^ Iiinninan
Transactions, toI. zzt, p. 400.



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relaHom of the Human Hand. 45

oi^ans which are central or proximal, simple^ rvdimeniary, and
oonstani; while teleology displays itself in organs which are per-
ipheral or distal, complicated And subject to variation.

10. Man is the most perfect animal in a functional point of
view, and the hand iai)eripheral in its position, complicated in
Junction and svbfect to variation both in the zoological series and

by arrest or excess of development : and forasmuch as it has,
during all ages and b^ all classes of minds, been regarded as a
typical illustration of perfection of detail and harmonious ar-
rangement of parts in strict conformity to the elevated offices
which it performs, therefore to the same extent must we disregard
it in our endeavor to determine questions of morphology,

11. Hands And fe^ but especially the former, are as unsafe
guides to the homology of the liml>8, as the cranial and caudal
regions would be to the characters of a typical vertebra.*

12. In discussing the relation between the fore and hind limbs,
we must 6*06 our morphological comparison firom all considera-
tion of special function.

13. The fore and hind limbs are appendages of the anterior
and posterior regions of the body; and whatever general laws
are ooserved in &e body, are, on a priori grounds, to be looked
for in the limbs.

14. Polarity, or something analogous to the polar forces of
physical science, is a primary law in the formation, the struc-
ture and the general functions of the vertebrate body ;f for the
existence of this, evidence is furnished by embryology, anatomy,
physiology, and pathology.:^

16. The anterior and posterior regions of the body are, as it
were, the two poles of a longitudinal axis, and their constit-
uent parts are more or less completelv homologous, repeating
each other in opposite directions like the corresponding organs
upon the right and left sides.

16. This polar or antagonistic relation of similar parts may
aasily be traced in the proximid segments of the limra in many
mammalia ; the front of the thigh and the convexity of the knee
are readily compared with the back of the upper arm and the
convexitv of the elbow.

17. Of the two pair of limbs, the anterior is the more subject
to variation and is therefore less reliable for morphological pur-
poses.

* Od a cat with Bapenmmenury digits; Prooeedings Boat Soa of Nat Hiit, Maj
le, 1866.

f See the writixwi of Oken: also deeoription of a double fiBtna, by Prof. Jeffiriee
Wyman, Beet Hed and Smg. Journal, March 29, 1866; and daasi&aiion of Her-
biTores, and Gepbalization, by Prof. James D. Dana, this Journal, vol zzzrii, p. 168,
and ToL zU, p. 164«

X See paper by the writer on Patholorical Polarity, Bost Med. aad Smg. JonMi],
April 6, 1866, and on Morphologr and Teleology especially in the limba of Maan-
maUa, Memoirs Boat. Soo. Nat Hist,ToL i, Na 1, 1866.



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46



B. G. Wilder on the Morphological



18. By reference to the less modified hinder limb we find that,
as a rule, tux> corUiguoua segments bend in opposite directions,

19. By comparing the proximal segments of the hinder limb
with those of the fore limb, we find that ttvo corresponding seg-
ments in the two limbs point and arejleoced in opposite directions,

20. Conformity with these two rules is all that would be ne-
cessary for maintaining the balance of a geometrical figure or a
stationary being; but to enable an animal to moye^ the terminal
segments of lx>th limbs must face in the same direc|;ion ; in the
quadrupeds this is usually accomplished by a rotation of the ra-
dius upon the ulna so as to fisu^e tne palm backward, or as in the
Aye-aye inward^ like the sole.

limbs of Iflft tide of Aye-ayo {OhmT<my% MadagoKmnemU Out.), (altered from

Owen.)*

AS C




▲, Fore-leg in naiuir€l atiUudt, the hand being more or leas pronaM,

B, Fore-leg in normal pontiorif the hand iupincUed so as to be symmetrical with
the foot

C> Hind-leg. S, Scapula ; I, Iliam ; H, Hmneros ; F, Femur ; O, Olecranon ; P,
Patella ; U, Ulna ; T, Tibia ; B, Radius ; Fi, Fibula.

Homologous parts are joined by continuous Ibes. Analogous parte are jomed by
dotted lines. The homologous digits of B and are numbered 1, 2, S, 4, 6,
starting from the so-called uttle finger and neat toe. The Roman numenli
attached to the digite of A indicate tiieir analogies with those of C.

* Menegraph of the Aye-aye, plate vii: Comp. Anat. and Physiology of Terte-
bratos, vol. ii, fig. 84S.



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relations of the Humaii Hand. 47

21. This is the natural aUitude of the terminal segments of
the fore-limb, but that it is not a normal position* in which they
may be compared with their posterior representatives, is seen
firom their want of conformity to the principles manifested by
the less modified hinder limb and by its own proximal segments
(Propositions 18 and 19), and also from the more or less com*
plete crossing of the two bones of the fore-arm, while those of
the leg are parallel with each other.

22. These three discrepancies are wholly removed by supina-
ting the hand and placing it, palm downward with the fingers
pointina backward and the vnnst in front jast as the toes point
forward and the heel is behind.

23. The ulna is now wholly upon the inner side of the fore-
arm and corresponds to the tioia while the radius corresponds to
the fibula; their variations as to size and shape and their being
solaered together in many species are all teieological modifica-
tions and ought not to enter into the discussion of a morpholo-
gical relation.

24. The thumb is thus lefii upon the outer side of the hand
and corresponds by position with the little toe^ while the little fin-
ger is upon the inner side and corresponds with the great toe,

25. These correspondences are, in my opinion, the true homol-
ogies while the relation between the ulna and fibula, the radius
and tibia, the thumb and great toe are merely analogies and de-
pendent upon teieological modifications.

The paper contained a more extended diflcus&ion of aome points and a
review of the later European memoirs upon the subject ; but in the hope
that we may shortly be &vored with the views of Prof. Jeffries Wyman
upon the important questions involved, the writer confines himself for the
present to the foregoing abstract with the following additions as the rt-
Bult of subsequent investigations.

A. The conclusion reached as to the normal position and ho-
mology of the thumb, though contrary to the common opinion,
is confirmed by all purely morphological considerations.

B. The lack of exact correspondence between the carpal and
tarsal bones in most mammalia and between the nerves and the
arteries in the human hand and foot where alone they have been
compared, is due to teieological modifications, the necessity for
which is yet to be explained.

C. The difference in the number of phalanges, which has
always been looked upon as a very essential distinction between
the tiiumb and great toe and the other digits, is really, like the

* For a forcible statement of the necessity for diatinffuisbing between the natond
attitude and the normal position of animals, see Agaasu's contributions to the Nat.
Hist, of TJ. S., vol. iii, part 1, p. 76 ; it throws a great light upon this relatloa of
the limbs.



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48 E. BilKngs an the Genus Aihyris.

Sneric variatioDs as to the number of the digits themselves, a
Serence of quantity and therefore teleological in its character.
D. Finally, even if there were not many vertebrates in which
this difference does not exist, and if there were not on record
Bevei;al cases of human thumbs having three phalanges, yet,
unless we are prepared to sacrifice position to quantity, we have
no more reason for denying the homology of the thumb and

Esat toe with the little toe and little finger respectively than we
ve for denying a homology between the third finger of man
and that of a whale because the former has some additional pha-
langes, or between the foot of man and that of a dog because the
former is composed of five digits while the latter has but four.



Art. VI. — On the Classification of the subdivisions of McCoys Ge-
nus Athyris, as determined by the laws of Zoological Nomenclature ;
bv E. Billings, Paleontologist of the Geological Survey of
danada.

[Bead befora the Nat Hist. Soc, Montreal, March 26, 186*7.]*

EVEBT naturalist who has studied the paleozoic brachiopoda is
aware that there exists a very great diversity of opinion with re-
gard to the classification of the several sections into which the
old genus Athyris has been divided. The arrangement which I
and some others have adopted is, in substance, the same as that

fToposed by Mr. Davidson in the first edition of his " General
ntroduction," published in ISSS.f Although this has been ob-

* After the reading of this Da|>er the sabject was diacnssed bj aome of the mem-
ben of the Sodetr. The following is from a abort report published in the new»>
papers at Montreal : ** After the paper was read. Dr. r. P. CarpeDter said that be
thoQght that Mr. Billings had clearly established his point, and gave an account of
the history of a committee appointed by the British Association to make laws to
regulate scientific nomenclature, of which committee he was a member. Mr. Whit-
eaves stated that he was satisfied with the correctness of the view Mr. Billings had
taken, and made aome remarks about scientific nomenclature, and upon some stmo-
tnral points in the shells of the genus in question. Principal Dawson deplored the
confusion that has arisen through conflicting views on the question of nomeodature,
and agreeing with Mr. BllllDgs in the conclusion he had come to, said that this
communication was valuable inasmuch as it cleared up a question that had hitherto
been rendered obscure."
f Mo<Ufied by separating Meritta thus :

QwKiM. TrPH.

Athyrii McCoy. 1844, A. tumida Dahnan.

Bpirtgtra D'Orbigny, 1847, - - - - S. etmeefUrica von Boeh.

Meriata Suess, 1861, M, IfereuUa Barrande.

The recent classification diflfors from the above as follows :

Meriitella Ball, IB60, A. tumida,

AthyrU or Spiriffera, - • - - iS. eoncmtriea,

MerUta, M. H§reuUa,

According to this, either Athyrii or Spiriffera must be suppressed, in order to
make room for MiriiteUa, See this Jour., [2], zzxi, 292, xzziii, zzxvi, 11



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E. BiUings on the Genus Athyris. 49

jected to by several distinffuished paleontologists, ^and in conse-
queace thereof, abandoned py its author, yet I believe that on a
careful examination of all the circumstances, it will be found to
be perfectly just toward the parties concerned, and in no respect
inconsistent with the rules of zoological nomenclature. It was
the first subdivision of the genus published, and should therefore
take precedence over all others.

Previously to 1853, Athyris was only known as a single large
genus of brachiopoda which included such forms as Terebratula
concenirxca von Buch, T. tumida Dalman, and T, Herculea Bar-
rande. In that year Mr. Davidson divided it into two smaller
genera, confining the name Athyris to that section for which it was
most appropriate, with tumida or Herculea for the types ; and
adopting Spirigera D'Orbigny for the other type, T, concenirica.
It was afterward found that Athyris, as then re-defined, included
two genera, and in consequence it has been again divided by
separating all those typifiea by T. Herculea under the name of
Merista, a genus proposed, but not clearly characterized by Prof.
Suess, in 1851. This is the classification which I believe to be
the true one. While discussing it I shall, throughout thiS pa,per,
when I mav have occasion to refer to the species above-named,
designate them, Athyris tumida, Spirigera concentrica, and Merista
Herculea,

Those who are opposed to this arrangement contend, that as
all the species which McCoy placed in the genus, at the time he
first described it, belong to the group typified by S. concentrica,
the name Athyris must be retained for that group, and cannot
now be transferred to the other section of which A, tumida is the
type. This reasoning, according to my views, can only hold
good in case it be first proved that McCo^^pecially confined the
genus to species having the generic characters of those in his
original list, or pointed out one of them as the type, or drew up
his diagnosis in such a manner as to exclude A. tumida. In
this paper I shall endeavor to show : —

1. Triat McCoy did not limit his genus to the species first
placed in it.

2. That on the contrary he and other naturalists understood
it to include both A, tumida and S. concentrica.

3. That according to the laws of zoological nomenclature the
subdivision made by Davidson in 1853 cannot be set aside.

4. That Davidson's classification has been adopted into several
works, some of them of great influence and wide circulation.

In order to prove the above propositions, I shall give the more
important facts of the history of the genus, with McCoy's original
figure, and shall quote some of the laws above mentioned in full.
Much of this, of course, belongs to the common stock of knowl-
edge of all paleontologists conversant with the fossils of the older
Ax. Jour. Sci.— Second Sssixt, Vol. XLIV, No. 180. - Jult, 1867.
7



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50 E. Billings on the Genus Aihyris.

rooks, and might be thought superflaoos. Bat the qaestion is
somewhat complicated and cannot well be decided, unless in
view of all the circumstances. Besides this, it is one upon which
any good naturalist is perfectly competent to give an opinion,
although specially engaged in other departments. Few of these
have access to works on paleozoic fossils, and therefore for the
convenience of such as may feel inclined to investigate the sab*
ject, it is desirable to bring all the facts togather.

There is no dispute about the extent of the genera, and there-
fore, the details of the internal characters need not be given.
It is purely a question of Natural-History Ethics, if I may be
permitted to use such a term.

1. History and extent of the original Genus, — The original de-
scription was published in the " Synopsis of the Carboniferous
Fossils of Ireland" in 1844. From this work I shall make some
extracts, and shall introduce alon^ with the original figure two
others to farther illustrate the subject.



Fig. 1 — Copy of tbe original figure tAven bj McOoj (without a apedfic mim) to

illiwtrate his idea of the geDerai form of ao Athyrii,
Fig. 2 — Spirigera coneerUriea von Buch. The form is copied from Davidaoo's Mooo-

graph of the British Devonian Brachiopoda, pi. Ill, fig. 18, PaL Soc. for 1861.

Tbe right-hand side is, in this copj, a little restored, and the apertnt m Us

beak made larger than it is in the original figure. , ,

Fig. S^ Athyrii tumida DaUnan. Copied firom Davidsoo's " General Introdocftioe,

pL VI, fig. 78.

The following extracts are fix)ni McCoy's work above refer-
red to : —

''The familj Deltkyridcs appears to be divided into the five following
genera: 1. Spirifera Sow., compoeed of those longitudinally-ribbed spe-
cies, in which the hioge-liae is equal to, or ezc^s the width of tlM
shell, the cardinal area with parallel sides, the cardinal teeth of the t«d-
tral valve (now cailed the dorsal valve) large, spirally rolled, and baring
a triangular foramen beneath the beak of toe dorsal (ventral) valve.
2. Afartinia McCoy, or the smooth Spirifers, in which the hin^^e-Une ii
less than the width of the shell, and the cardinal area tnangulsc
8. Athyris McCoy, in which there is no vestige of either foramen, cs^
dinal area, or hinge-line. This remarkable genus is frequently oonfoonded
with those shells usually named Terehratukiy in the older rocks, bat v
distinguished by the large, spiral appendages, which are wanting in tiM



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E. Billings on the Oenus Atkyris, 51

other ffroQp. 4. Brachythyris McCoy, in which we find the longitudin-
ally-ribhed surface of Spirifera, united with the short hinge-line of Mar-
tinia, 5. Orthis Dal^ in which there are no spiral appendages, the
hinge-line and striae frequently spinose ^as in Leptama)^ and the cardinal
area common to both valves, and its sides inclined toward each other at
its angles; dorsal valve smallest." — Op. cit., page 128.

On page 146 of the same work, he thus concisely describes the
genus: —

^ Gm, Ch, — Nearly orbicular, small ; no cardinal area or hinge-line ;
spiral appendages very large, filling the greater part of the shell.

^ This very interesting group possesses all the external characters of the
TerebratulidcBy united to the internal structure of the Spirifers, to which
latter family it truly belongs. Professor Phillips is the only author who
has recognized the group : he forms of it his last division of the genus
SpiriferOy but gives no characters to distinguish it from Terebratula ;
the internal structure is, however, a sure guide."

The above is all that he wrote about the genus at that time ;
and it will be perceived, that he does not point out any partic-
ular species, asthet^^pe: and farther, that there is nothing in
his remarks from which it can be inferred that he knew any-
thing about the genera into which the ^roup was afterwards sub-
divided. Consequently, it is impossible tnat be could have in-
tended to confine the genus to any one of them ; as is now af-
firmed by some of the naturalists who are opposed to the class-
ification advocated in this paper. Instead of excluding species
with an imperforate beak such as A. tumtda, the etymology of
the word Athyris (without a door or opening), the expression,
'' in which there is no vestige of either foramen, cardinal area
or hinge-line," and, also, ms typical figure all induce the belief
that he had before him one or more forms with the beak entire.
This is rendered certain bv what he says on page 147. Speak-
ing of what he calls A. coiicentrica, he says: '*This species is
not uncommon ; it is figured in the Bull, de la Soc. G-^1. de
France, with a perforated beak as in Terebratula. I have, how-
ever, seen numerous specimens with the beak entire and imper-
forate, as in the other raleozoio species." It is highly probable
from all this that he had in view such Silurian forms as A. tvr
mida. This latter species is so common that it is almost certain
that such a collection, as he was then engaged upon, would con-
tain one or more specimens.

If we take the paragraph (No. 3) as a part of the generic de-
scription, then A. iumida is included. If, on the other hand,
we confine ourselves to the extract from p. 146, it is not exclu-
ded, as there is no reference made there to the structure of the
beak. This latter diagnosis is sufficiently comprehensive and
general in its terms to include Athyris, Spirigera and Meriata.
He did not place A, iumida in the genus, for the reason that his



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52 E. Billings on the Genus Athyris.

work was confined altogether to the Carboniferous fossils, among
which it does not occur. But he did so afterward when he de-
scribed Professor Sedgwick's Silurian fossils, as will be shown
farther on. He was wrong in supposing that all the species
were imperforate, a matter of little consequence, as it was sim-
ply an error of observation which does not vitiate. Had the
Senus turned out to be not capable of subdivision, all that could
e done now with this error would be to strike it out. There
was sufficient in his diagnosis to indicate what group of fossils
was intended. He was also wrong in supposing S, eoncentrica to
be a Carboniferous fossil : it is Devonian. It may be that he
mistook some other species with an imperforate lieak for that.
It will be seen farther on that Prof. King made a similar mis-
take with respect to this very species, having taken T, scalprum
Barrande, for it ; an error wnich was detected by Mr. Davidson.
Altogether, he referred eleven species to the genus, several of
which have been shown to be synonyms.

In the same work he proposed another genus, Actinoconditis^
but as it was founded on error, he afterward withdrew it> and
added it to Athyris. (Brit. Pal. Foss., p. 486). All scientific works
abound more or less with such misconceptions.

That the genus was understood by other naturalists to include
A. tumida is proved by the following facte. It is well known
that the genus Spirigera was proposed by^D'Orbigny, in 1847,
simply as a substitute for Athyris^ on the ground that this lat-
ter name implies the absence of a foramen, and is, therefore,
not appropriate for species with a perforated beak. It is quite
clear that D*Orbigny considered his genus to be precisely the
same in extent as Athyris, All the species, therefore, which
he placed in Spirigera he regarded to be fairly within the group,
.and it is unquestionable that he would have referred them all
to Athyris had not that name appeared to him objectionable.
I have not seen his original description in the "Annales des
Sciences Naturelles," referred to by Mr. Davidson, in the ex-
tract given below, but in the " Pal^ntologie Frangaise," vol.
iv, page 367, he says : " This division has already two generic
names which we cannot preserve, because they are in complete
contradiction with zoological characters." The two genera re-
ferred to were Athyris and Actinoconchis.

He specially selected T. eoncentrica* for the type of his genus,



Online LibraryJohn AlmonThe American journal of science and arts → online text (page 56 of 102)