90 
FIRST CLASS OF THE VERTEB RATED ANIMALS. 
AnimaJs of cold coaidries approach towards this ppcuHarlty of the Sheep. In warm 
regions, on the contrary, the bristly hairs are more strongly developed, and the woolly 
hairs become almost wholly wanting. The quantity, or rather the proportional abun- 
dance of the latter, is generally in the inverse ratio of the temperature, while that of 
the former is directly proportional to it, or nearly so. 
The climate has a great influence on the nature of the hair, especi.ally among the do- 
mestic animals- It becomes long and rigid in cold regions, as we remark in the Sibe- 
rian Dog and Iceland Uam. Syria and Spain produce an opposite effect, and these more 
favoured climates produce a corresponding change in the hair, which may become 
tufted, fine, and silky. These qualities may be remarked in the Spanish Sheep, the 
Maltese Dogs, as well as in the Goats, Cats, and Rabbits of Ar^ora, 
The coarser hairs bear a greater predominance in certain parts of the body, especially 
among the Males, such as in the cervical region of the Lion and Horse, where they form 
.a mane, and on the tail in many species. Other animals are covered in every part 
of the body by very long hairs ; such, in particular, is the Bear of India ( Ursus lalia- 
in which the hairs are almost every where from seven to nine inches in length, 
and in some places even a foot long. 
In some specie? the fur is mixed, and in others it is sometimes composed entirely 
of spines, more or less abundant, and of various structure; such are the Hedgehogs, 
the Tenrecs, the genus Echimys, the Porcupines, and many others. These spines 
or prickles are usually pointed, as their name indicates, and eat^h is composed in 
general of a single hair. A great development of the muscles of the akin is always 
found in all species armed with spines, and this arrangement is especially remarkable 
in the Hedgehog. It may also be observed, on comparing different species, that the 
spines arc arranged in small and regular groups, tlie disposition of which is peculiar 
in each species. 
It becomes difficult to examine the structure of the hairs on the human body, be- 
cause they are slender ; but the bristles of the Hogs or the whiskers of the Cats are 
better adapted for this kind of inquiry. On cx.'imiuing the bristle of a Wild Boar 
with the microscope, we observe that it is grooved throughout the wliole of its length 
by about twenty furrows, formed by an equal number of filaments, and the union of 
which constitutes the surface of the hair. In the middle of the bristle there are 
two canals, which contain a humour called th<; pith or marrow. The filaments of tlic 
hair separate on being dried, as may be remarked in the bristles of brushes, where 
the cavities may be observed to be empty, and a few lamina.* cross each other in dif- 
ferent directions. 
The hairs of the Elk and Musk, with the spines of the Hedgehog, the Tcnrce, and 
the Porcupine, are not altogether similar ; their surfaces being covered with a horny 
lamina, varying in thickness, atid a few furrows only < an be observed. Internally 
they contain a white spongy substance, which appears at first sight strongly to re- 
.«5cmble the pith of the Elder-tree (’Sambneus 7ti^ra). 
The colour of the hair appears partly to depend upon that of the raucous tissue ; 
for where animals have differently coloured spots upon the hair, these usually indicate 
corresponding colours below them in the skin. Even in the human species, many 
striking relations of this kind tpay be remarked. Thus, Ne;jroes in general have the 
head black. Persons with red hair often have the skin freckled or covered with red- 
dish spots, while black hair usually accompanies a dark complexion. 
The external colours of Animals depending on those of their respective mucous 
tissues are exceedingly various. Among the Mammalia, it is very seldom that th»*y 
appear of a vivid hue. On some species of Mandrills, the nose and hips are bright 
rfd, violet, and carmine. The raucous tissue is also pure white on (heir cheeks; and 
of a beautiful silvery whiteness on the bellies of the Cetacea. In the Mammalia gene- 
rally, the mucous tissue imparts its hue to the hair and nails. It is often observed to 
be i-olourcd within the cavities of organs, into which it has been prolonged, such a.s 
on the palate, the tongue, the ear, the conjunctive and nasal membranes of the Quad- 
ruraana, Dogs, Rmninanfia, and Cetacea, The mucous tissue appears to be thickest 
in the class last mentioned. On the backs of the Dolphins and Porpoises it is very 
thick, and of a deep black. 
The colours of the Mammalia have not that metallic lustre which characterises 
a large number of the genera of Birds, there being one solitary exception to this ob- 
servation in the brilliant lustre of the Chrysochloris, or Cape Mole. Wo do not find 
among these animals the dazzling brightness of the Parroquets, the Tanagers, or the 
Flamingos, nor can we discover anytliing analogous to those ornamental appendages 
which adorn the plumage of many Birds. There is another peculiarity in the colours 
of the Mammalia, that they are in general much paler and fainter beneath than on 
the back or flanks. Tliis may be observed not only in the true Quadrupeds, but even 
in those species, such as the Kangaroos, which more or less are in the continual habit 
of maintaining an upright position. Yet, without enumerating all those species which 
are entirely of one colour, such as the Coaita (/lleles panUcits), the Polar Bear 
(Ursus maritimus')i we find some exceptions among the Rodentia, and especially in 
the order of Carriassiers, such as the Hamster, the Gluttons, the Badger, and some 
other species, while many even have the belly absolutely black. In particular, we 
mav notice a Carnassicr recently ilescribod, for tlic first time, by M. Frederic Cuvier, 
who has assigned to it the specific name of Panda. 
The colours of the males among the .Mammalia are most commonly the same as 
those of the females, excepting perhaps that the shades of the latter are not quite so 
deep. In this respect thev differ remarkably from the greater number of Birds, iu 
which the colours of the female differ almost ivholly from those of the male. How- 
ever, all the other circumstances which influence the colours of Birds act equally 
upon those of the IHammalia, although most commonly in a different manner. Age, 
tor example, varies the colours of the fur only in a small number of species, as among 
the Stags, the Tapirs, and the Lion, all of which are clothed at their birth in a kind 
of livery, or peculiar aiTangement of colours. Tlieir coats, instead of being uniform, 
as in the adults, are at first ornamented with spots, regularly disposed, and analogous 
:n their arrangement to those observable in the adult animals of other species belong- 
ing to the same genus. Thus the spots of the young Fawns are white, similar to 
those of the adult Axis; while they are black in the Lioness cubs, in the same man- 
ner as we see in most adult Cats. This very remarkable relation between the system 
of colouring belonging to the young individuals of one species, and that observed in 
other species of the same genus, may also be traced among the Birds. But the young 
of the Mammalia differ from those of Birds in this respect, that — while the plumage 
of the latter, most commonly resembling that of their mothers, is duller in its hues 
than at a more advanced period of life — the livery of the young Mammalia is, on the 
contrary, an ornament which they gradually lose as their years advance, until they 
finally resign the spotted and agreeable garb of youth for one of a more simple and 
tmifonn character. 
The colouring matter of the hairs resides in the horny part of their substance, and 
not in the pith, which is commonly white. We c.in observe tliis structure most con* 
veniently in the spines of the Porcupine, from their unusual magnitude. Some hairs 
are coloured differently in several pai-ts of their length, while the colours themselves 
may be inlinitely various, both iu quality and intensity. In general, the hairs of the 
Mammalia are round, and this form is observed more especially in the hair of the head 
or mane. On tho tail of the Hippopotamus, as well as on the body of the Great Ant- 
eater, and especially on the Ornithorhynchus, they assume a flattened appearance ; 
and in several species of the Ruminantm, especially the Musk (Moschtis moschi^ 
ferns), the hairs appear as if they had been crimped. In 5(*me varieties of Goats, 
Cats, and others, the hairs are fine, long, and silky; they appear both crisped and 
frizzled in the Rams. From their great thickness, stiffness, and elevated position 
in the Hogs, Hedgehogs, and Porcupine.**, they have received the name of Spines 
in the two last-mentioned animals, and of Brislles iu the first. 
All Mammalia possess a certain quantity of hair, without excepting the Cetacea, 
in general destitute of this covering. Man is covered in almost every part of the body 
by scattered hairs, although they are net easily perceived in some places from their 
excessive fineness. Those of the head and beard are the longest; those of the axilla 
and pubes are next in length. On tho interior of the nose and cars they arc 
shorter, and on the remaining parts of the body they appear of a still more dimimn- 
tive length. Contrary to the arrangement in the other Mammalia, the hair is longer 
on the breast and abdomen than on the back. There is never any hair on the palms 
of the hands or on the soles of the feet. 
Among the Quadrnmana, the true Apes have the hair of tho head in general of the 
same length as that of the body. The hairs which cover the fore-arm point upwards 
towards the elbow, instead of being directed towards the hand, as we may see in the 
Orang-Outang and some other species. The buttocks arc callous in a great many 
Quadrumana, and entirely deprived of hair. 
In most species of Cheiroptera, a few scattered hairs only can be seen on the mem- 
branes of the wings, the nose, and the ears. One species of Bat P'espertUio lasu 
urus, Linn.) has also a few upon the tail. The remainder of the body is covered 
by short, fine, and villous hair, as may be seen in the Flying-cats ( Guleopitheeusjt 
and other animals of their order. 
The spines of the Hedgehog are found only upon tho head and back ; the limbs and 
lower parts of the body are covered with stiff Ijristles. In these respects, the Tcrirecs 
resemble the common Hedgehog. In some sj)ecies the spines and bristles are mixed 
tog»‘thcr indiscriminately. 
The h;ur is fine, short, and close in the Moles and S/irews, so that their skins seem 
as soft as velvet to the touch. 
Among the Carnivora the hair varies considerably. There are two kinds of hair 
in the Weasels, Sables, Ermines, Martins, and others ; the one being very fine, thick- 
set, intermixed, and placed close to the skin ; while the other, which is longer and 
stiffer, alone appears at the surface. These two kinds constitute the finer furs. The 
amphibious Mammalia have short, rigid, and very close hair. 
The arrangement found in the Carnivora may also be remarked among the finer 
haired Rodentia. Tlic spines of tho Porcupine arc more slender, short and flexible 
on tho head, neck, and belly, than on the back. There arc about ten or twelve placed 
upon the tail, and resembling the tubes of quills, truncated at the free extremity. A 
rustling sound is emitted from these spines w'hen the animal moves its skin. 
Among the Edentata there is found a considerable diversity in the quality of, the 
hair. It is broad and flat in the great Ant-eater (Mj/rmectjphapa Jubaia), and has 
a longitudinal furrow in both surfaces, so that each hair presents the appearance of u 
dried blade of grass. Tho two-toed Ant-eaters are covered, on the contrary, w ith very 
fine wool. Several have hard and sharp-edged scales placed one over another, like the 
tiles of a house, as we see an example ifi the Mauls. Others are covered with prickles* 
like the spinous Ant-eater (Echidna). The Armadilloes (Dasppm)hAvc, in addition 
to the scales or osseous bands, which cover the back and head in regular compart- 
ments, some scattered hair?, which are short and rigid like those of the Elephant. 
These hairs drop off, however, as the animal advances in age. 
The Hogs, of all Pachydermata, have tho greatest quantity of hairs, which in them 
are called bristles. 'J’hese arc scattered and frequently bifid at their free extremity. 
The other genera of this family are comparatively almost destitute of hair. It is in 
general short in the Solipeda, excepting on tho mane and tail, where it receives 
the name of Horse-liair (crines). 
'I'hn Bulls, Deer, Antelopes, and Giraffe, have short hair in general. In tho Ca- 
mels it is very fine and soft, and remarkably so in the Lamas. All of them may 
have callosities, which are destitute of hair, on the knees and breast. Goats’ hair is 
long and fine, extending to a pointed beard under tho chin. The hair of Sheep i* 
long, and readily distinguished by that crisp and frizzled appearance, well known hi 
the wool of commerce. 
1'he Hair of all these animals, when submitted to a chemical analysis, yields nearly 
the same results, whether it be examined under the form of wool, bristles, spines, 
or scales. On being subjected to the action of Heat, in open vessels, it fuses or h" 
quifies .at first by swelling up. It subsequently emits a white flame, and resolves into 
a black carbon, the incineration of which is very difficult. Hair yields, on distilla- 
tion, a reddish liquor, containing prussiate of ammonia, and another salt of an am- 
inoniacal base, combined with a peculiar animal acid, which Bcrthollet has named 
Zoonate of Ammonia. The carbonaceous residue at tho bottom of tlic still is ligh’, 
and contains carbon and phosphate of lime. The Iliir docs not dissolve completely 
in boiling water, a mucilaginous matter, which is the pith or medulla, being sepa- 
