REMARKS ON THE FIGURES OF PLATE LII. 
homologues. Under the joint operation of both these laws 
of uniformity and metamorphosis, the reason can never 
account for that variety which distinguishes two or more 
entities from one another; such as a muscle, a bone, or a 
nerve in the animal body, or such as a leaf, a feather, and 
a ligament in different organised beings. A muscle, a 
bone, a nerve, a leaf, a feather, and a crystalline lens, are 
what we here understand to be things so absolutely diverse 
to each other, that they can never be subjected to the rule 
of analogy or interpreted under the same common law.* 
But granting thus much to the actuality of special variety 
originally founded in nature, and granting also that to 
take account of the chemical and functional characters of 
structures thus created diverse be the lawful province of the 
physiologist, we believe that the science of formation which 
the morphologist or comparative reasoner pursues through 
the graduated series of structures created of the same 
physiological identity, such as an osseous piece or an 
osseous framework in all animal bodies, which produce the 
like, may claim a place amongst the first within the terri- 
tory of reason. It cannot be denied that the osseous 
quantities of the skeleton serial axis manifest an analogy 
to each other, despite the fact of their variation as to quan- 
tity, nor can it be denied that all the varieties which 
characterise all skeleton axes are only those which may 
occur by the metamorphosis of quantity at different regions 
of series, or to different degrees upon each unit in series ; 
therefore, these facts may be interpreted under a common 
law of formation. This law which, there is every reason to 
believe, is one of rendering a plus uniform serial line of 
quantities proportionably various by the subtraction of 
elements, is that which we are seeking to establish in refe- 
rence to the endo-skeleton axis only. 
This osseous fabric, which we find to be produced within 
the bodies of certain classes of animals, is that particular 
alone to which our observations tend. The law which 
governs its development, and presents it to our notice as a 
unity in variety, is that subject which alone interests us in 
this place, and to this we look for information. It is 
necessary to set this limitation to our subject; for we 
conceive it to be no less essential to the development of 
knowledge to define the character of those entities which 
agree with each other, and disagree from all the rest, than 
it is to particularise one order of study from another and 
distinct order. When we engage in inquiry after the law 
which presides over the structural designs of osseous quan- 
tities, we do not include amongst those. designs any 
other parts which are not of this structural growth; such, 
for example, as the dermal covering, &c., but we here 
separate these as distinctly the one from the other as we do 
the subject of anatomy from that of metaphysics. The 
law which gives creation to the tegumentary membrane 
throughout the series of an animal scale, can no more 
teach us of the law which rules the creation of endo- 
. 3 
skeleton formation throughout the serial line of these 
figures, than can the laws which govern psychical phe- 
nomena yield to us an insight of the laws which mani- 
fest themselves in the animal economy. Bone refers 
to bone in a connected argument, and wherever we find 
bony tissue we never find tegumentary tissue, and. there- 
fore we isolate our remarks to the osseous 
quantities. 
skeleton 
It is true that all structures whatever which 
are to be found in the animal entity bear a certain 
relation to each other, as being related to the one living 
body, just as all the physical sciences have a connection 
amongst themselves, owing to their common bearing in 
the body and framework of the gvois: it is true that, in 
order to know ‘he all of the animal ens, we are required 
to investigate the sum total of its structural variety, 
just as in order to understand the whole of the physical 
ens would require us to study all variety which in con- 
geries constitute it; but this mode of inquiry imperatively 
demands, first of all, that we should mark those distinc- 
tions between structures which Nature has actually 
created specifically distinct in the one body as well as 
in the other. The dermal covering, which in some 
animals has undergone such modification as to include 
them within a case of skeleton armour, and between 
which and the osseous skeleton some anatomists have 
drawn analogies, is nowhere in serial Nature seen to 
flux and confound itself with this latter. The dermal 
skeleton is distinct from the osseous skeleton; the one 
never fuses with the other; and this being the demon- 
strable fact, we ask, who shall identify as entities of the 
same system, such structures as Nature herself creates of 
distinct species to one another? The philosophy of 
Geoffroy has not. made them one and the same. Again, 
who shall draw the differential lme between structures 
which, to the commonest observer, seem evidently to 
blend with each other, such as the fibrous tissue, cartilage, 
and bone, and which so completely obey the law of 
phaseal transformation that the first or fibrous gives place 
to the second or cartilaginous, and this to the third or 
osseous? The reputation of Cuvier has not rendered them 
distinct from each other, nor obliterated the written fact 
from the chart of Nature or of science, that in the 
intimate connection which fibrous substance, cartilage, 
and bone manifest throughout the endo-skeleton system, 
resides one of the principal illustrations of the law of 
osseous skeleton formation. 
The transcendental anatomists have drawn analogies be- 
tween structures which Nature holds specifically distinct, 
not only in the body of one animal, but from one 
extremity to the other of the graduated scale of being. 
They have overstepped the differential line which Nature 
herself draws between structural distinctnesses, and have 
identified those structures as one, which Nature never 
confounds together, either by a oneness of place, a one- 
* “Tenique illud omnino precipiendum est, et sepius monendum, ut diligentia hominum in inquisitione et congerie naturalis historic 
deinceps mutetur plane, et vertatur in contrarium ejus, quod nune in usu est. 
Magna enim hucusque, atque adeo curiosa fuit hominum industria 
in notanda rerum varietate, atque explicandis accuratis animalium, herbarum, et fossilium differentiis ; quarum plereeque magis sunt lusus nature 
quam seriz alicujus utilitatis versus scientias. 
Faciunt certe hujusmodi res ad delectationem, atque etiam quandoque ad praxin; verum ad 
introspiciendam naturam parum aut nihil. Itaque convertenda plane est opera ad inquirendas et notandas rerum similitudinis et analoga, tam 
integralibus, quam partibus; ill enim sunt, que naturam uniunt, et constituere scientias incipiunt.”—Bacon, Novwn Organum, aph xxyi. 
