58 
FIRST CLASS OF THE VERTEBRATED ANIMALS. 
It is evidont that we can only ascertain the effect which a very long time will pro- 
duce, by comparing it with the change actually observed to have taken place during 
a shorter period. MJI. Cuvier and Geoffroy- Saint- Hilaire sought out the most 
ancient documents which Egypt could afford, for the purpose of solving this question, 
so important to the Naturalist, and essential to a knowledge of the past history of our 
globe. M. Cuvier examined with great care the ancient ^Egyptian obelisks trans- 
ported to Rome, and found a perfect resemblance between the general form of the 
animals engraved thereon, and the common species of onr own day. M. Geoffroy 
collected as many mummies of the lower animals and of Wan as he could find, and 
was led to form a similar conclusion. These monuments must have been from 2000 
to 3000 years old. “ For a long time,” says M. Lacepede in the report which ho 
made upon these objects in common with MW. Cuvier and Lamarck, — “ For a long 
time philosophers have been anxious to know whether species change their forms dur- 
ing the course of ages. Tins question, apparently trivial, is yet essential to the history 
of the globe, and to the solution of a thousand other questions not far removed from 
the gravest objects of human veneration. Never were we in a better condition to 
decide the question upon a great number of remarkable species, and for a long period 
of years. The superstition of the ancient iEgyptians would almost seem to have 
been inspired by Nature, for the purpose of bequeathing to us a monument of her 
history. A people of fantastical opinions, by embalming with so much care the 
brute beings, objects of their stupid atloration, have left in their sacred grottoes com- 
plete cabinets of zoology. Tlie climate has united with the art of embalming to 
preserve these bodies from all corruption, and we have now the means of ascertaining 
with our own eyes what was the condition of these animals 3000 years ago. One 
can scarcely restrain the raptures of Imagination upon seeing at the present day an 
animal preserved, with the smallest bone and hair perfectly distinguishable, which 
had 3000 years since in Thebes or Memphis its priests and altars. But without 
wandering into all the subjects to which these associations give rise, we shall confine 
ourselves to noticing the simple fact — that those animals perfectly resemble those of 
the present day.” 
Although the bones of a species do not vary to any extent, yet the identity of 
osteological characters i.s not alone sufficient to establish an identity of species ; and 
some species which possess a most exact similarity of structure are held, by the ge- 
neral consent of Naturalists, to be of different species. It is almost impossible to dis- 
tinguish the skeleton of the Wolf from that of the Wild Dog of New Holland. Their 
teeth are the same ; the vertebrae of the tail are equal in number ; the feet have the 
same number of toes ; and the bones of the head exhibit the same relations, except 
that the orbital fossae are slightly larger in the Wolf. The same thing occurs in the 
Wolf of Canada, which is smaller than the common Wolf, and larger than the Dog 
of New Holland. The Jackal also resembles the Wolf-Dog very closely, especially 
in the form of the head. There is likewise a most exact similarity in respect to the 
organs of Sense among the New Holland Dog, the Canadian Wolf, and the Jackal. 
Again, the quality and arrangement of the hair exhibit no essential differences, for they 
all may have either woolly or silky hair, according as they have been naturalized in cold 
or temperate countries. In fact, they only differ in colour. Yet all these genera 
merely vary from white to brown or bkek, and excepting the Black Wolf, which has 
the hair of a uniform colour, the others have hairs of fawn, black, or white so mingled 
together, that it is difficult to set down any colour as peculiar to either species, and 
which w'dl not pass by insensible shades into another. 
What, then, it may naturally be inquhed, forms the distinction between a species 
and a mere variety ; and how are wo to ascertain those permanent characters which 
were assigned to oim domestic animals at the origin of things ? 
If these questions be considered in a purely abstract form, no difficulty can arise, as 
we have only to include in the same species all those animals, whoso differences of 
external form and garb can ho traced to some acknowledged causes of variation ; 
while the animals whose differences cannot be thus explained, must be held to belong 
to separate species. “ WTiere two races of animals are distinguished by any undeviating 
marks in such a way that they never will, under any circumstances, pass into each 
other, or that the progeny of either can never acquire the characters of the other, they 
are of distinct species, and it matters not how wide or how narrow be the lino of dis- 
crimination, provided that it never be broken in upon.” But when we come to apply 
these abstract rules to the realities of Nature, we find that they are not always suffi- 
cient to distingrush the mere variety from the genuine species. 
The difficulty is further increased by the circumstance that many varieties or races 
of some species differ more decidedly among themselves, than the species of certain 
genera, where the objects are very numerous. Again, the greater part of our acquisi- 
tions arc imported from remote and barbarous countries. “ A largo proportion,” as 
Mr Lyell observes, “ have never even been seen alive by scientific inquirers. Instead 
of having specimens of the young, the adult, and the aged individuals of each sex, 
and possessing means of investigating the anatomical structure, the peculiar habits 
and instincts of each, what is usually the state of our information ? A single speci- 
men, perhaps, of a dried plant, or a stuffed bird or quadruped ; a shell without the 
soft parts of the animal ; an insect in one stage of its numerous transformations ; — 
these are the scanty and imperfect data which the Natur.aUst possesses. Such infor- 
mation may enable us to separate species which stand at a considerable distance from 
each other ; but we have no right to expect .any thing but difficulty and ambiguity, 
if wo attempt from such imperfect opportunitic.s to obtain distinctive marks for 
defioinw the charoctcr-s of species which arc closely related. When our data are so 
defective, the most acute Naturalist must expect to bo sometimes at fault, and, like 
a novice, to overlook essential points of difference, or pass unconsciously from one 
species to another,’* 
Buffon c 5 tal)U 3 bcd the criterion for the determination of species in the power of 
producing, by their union, races equally fertile with themselves, and this rule seemed 
to he couGnned by the experiments of John Hunter. Tliey were of opinion, that 
“ if a male and female produce an offspring which is prolific, the tribes to which the 
parents respectively belong are hence proved not to bo specifically different, and 
whatever diversities may happen to characterize them, are in this case to be looked 
upon as examples of Variation. But if the third animal be unproUfic, it is to be con- 
cluded that the races from which it is descended arc originally separate, or of distinct 
kinds. The fact that most hybrid animals arc wholly unprolific, would appear to be 
a provision for the attainment of this desirable end, and for maintaining the order 
and variety of Nature. For if sueh had not been the condition of these intermediate 
animals, wo have reason to. believe tliat all the primitive distinctions would have been 
long ago totally effaced ; a universal confusion of species roust have ensued, and there 
would not be at this day one pure and mimixed species left in existence. The Na- 
turalists above mentioned, inferring, from the apparent utility of this law, that it must 
universally prevail, obtain by means of it a ready method of determining on identity 
and diversity of species.” 
It is very clear that if two animals are prevented by any great disparity of organi- 
zation or disposition from uniting, that the criterion of generation holds good to a 
ccitain extent. The Bull and the Goat, for example, would at once be pronounced to 
be distinct species. This rule may enable us to assort that two animals arc not of the 
same species, but it does not always serve to discriminate between nearly-allied species. 
Hence it seems rather to be the first rude attoropt at forming a criterion, than one 
which serves to mark out nice distinctions. The crosses among the Dog, the Wolf, 
and the Jackal; — between the Goat and the Sheep; — the Horse and the Ass; — 
the Lion and the Tiger, with the occasional appearance of fertile Hybrids in many, 
and the possibility of its occurrence in them all, show that the converse often fails. 
Although animals which do not generate tc^cther belong to distinct species, yet it is 
not true that distinct species must not generate together, nor does it follow that their 
progeny must always be sterile. 
The determination of species by the property of producing fertile races, had previously 
been restricted by Frisch to such as generate together of their own accord, “ von Natur 
mit einandcr gatten.” Those artificial unions brought about by restraint, artifice, or 
domestication, were wholly excluded by him. But tlris restriction renders the rule 
useless in practice for determining those points where difficulties may chiefly be ex- 
pected to arise. It is in respect to Man and the domestic animals, or with animals 
brought from distant and uncivilized countries, that a rule is most required to distin- 
guish the species from tbo mere variety. Blumcnbach inquires, Wlien will it como 
to pass that all nearly-allied animals shall be brought together from remote countries, 
so as to submit them to the requisite experiments, — for example, whether the Chim- 
panse (Troglodytes niger) from the Angola Coast, will form a fertile race with the 
Orang Outang (Pithecus Saiyrus) from Borneo?” This is a desideratum which the 
general establishment of Zoological Gardens alone can supply, but in the meantime 
we must seek some other criterion, which shall be applicable to Man and the domes- 
ticated animals, for the determination of species. 
It is here that difficulties arise in drawing the lino between the species and the 
variety. Tillesius considers that several distinct species are confounded under the 
name of Jackal or Chacal (Ccmis aureus)y while both Pallas and Guldenstaedt re- 
garded the Jackal of Caucasus as the original source whence our domestic Dogs are 
descended. Others again tliought that the different kinds of Dog have diverged from 
the Shepherd’s Dog, while some considered them all but as degenerations from the 
Hyojna, the Wolf, or the Fox. 
Thus it is precisely in those places where a fixed rule is most required that the 
breeding principle wholly fails, and we may seek in vain for any other. Blumen- 
bach could propose none, but referred the determination of species to Analogy and 
Probability. “ Fere desperem,” he observes, posse aliunde quam ex Analogia 
et verisirailitudine notioncm speciei in Zoologi® studio depromi." (I may almost de- 
spair of being able to derive the idea of species in the study of Zoology from any other 
source than analogy and probability). Two races of animals which possess a general 
resemblance, ami differ only in those reepccls which have been observed to vary, and 
can be traced to some well-known causes of variation, must at once be admitted to 
belong to the same species ; but however near their general appearance may be, if 
they exhibit any difference which, in all our experience of the Animal Kingdom, has 
never been known to exist as a variety, they must be set down as distinct species. 
The proper determination of species rests, therefore, upon the knowledge of an im- 
mense number of facts, and forms one of the most difficult, as it is one of the most 
important, subjects to which the Naturalist can direct his attention. 
Thus Blumcnbach considers the Ferret to be merely a variety of the Pole-Cat 
(^yiu&tela putOTius)i not because they generate together, for perhaps the experiment 
may not yet have been made, but because the former is white with red eyes; and. 
from that well-known rule of analogy, that the same effects must be referred to the 
same causes, its origin ia the same with those Albino varieties produced daily among 
the domesticated Mammalia. Again, the Indian Elephant (^Klephas Indicus) differs 
remarkably from that of Africa {E, Africanvs) in the number and form of its molar 
teeth. Whether these animals will engender together it is perhaps difficult to deter- 
mine ; but on examining every specimen which reaches this country, the same differ- 
ence is found to exist. Further, we know of no analogous instance of variety in the 
formation of the molar teeth among wild or domestic animals. We, therefore, 
not hesitate to set down these two Elephants as distinct species. 
There are other difficulties arising from the want, of accurate information ; and these, 
in the present state of tho science, occur but too frequently. For example, the skin 
of an animal arrives from the Cape of Good Hope. At tho first glance it appears, 
perhaps, to be a specimen of tho common Cape Otter (Lutra capensis), and this 
opinion may be further confirmed on examining tho structure of its teeth. The colour 
of the breast and throat may seem of a purer white, and to bo more extensive than 
usual, but this b a characteristic which might belong to a more variety. On lookin^C 
at the feet, we are much surprised at finding all the toes without nails, excepting 
on the second and third of the hinder-feet, where only a rude vestige of a na*^ 
can bo observed. A Carnassicr without claws would seom an anomaly in creation- 
To suppose a being, compelled by its structure to live on animal food, and yet to be 
refused by Nature tlie weapons fitted for seizing its prey, disturbs our ideas of 
causes, and we delight to trace order and regularity in tho works of creation. 
specimen must then bo imperfect. It belongs to an old individual; — perhaps 
claws may have dropped off through age or disease. Wo set it down, therefore, 
as a mere variety of the Lutra capensis. Sqrae. years afterwards, young 
