An introduction to the study of mammals living and extinct / by William Henry Flower and Richard Lydekker.

Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to the study of mammals living and extinct / by William Henry Flower and Richard Lydekker. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    Lion accords well with the prevailing tint of its native desert; and any one who has seen an Elephant or Buflalo in the deep shades of.. an Indian forest will realise how perfectly adapted is their dull, slaty colour to concealment in such a spot. The dun colour of the Wild Ass of India is equally well suited to the sandy deserts of Kutch; it is also stated that the brilliant stripes of the Zebras of Africa are arranged in such proportion as exactly to match the pale tint which arid ground possesses when seen by moonlight.^ The most remarkable instance of protective coloration is, however, to be found in the Sloths of South America, in which the coarse gray hairs so closely resemble a mass of lichenous growth that it is almost impossible to distinguish these animals when at rest from the gnarled and lichen-clad boughs from which they suspend them- selves. This resemblance is increased by the fact that the hairs actually develop a growth af lichens upon themselves. That the sombre coloration of these animals has been produced to harmonise with their present surroundings seems to be evident by the circum- stance that when the long hair is plucked <M the under fur is seen to present a bold alternation of black and yellow stripes, which may probably be regarded as the original primitive coloration of this group. Scales, etc.—True scales, or flat imbricated plates of horny material, covering the greater part of the body, so frequently occurring in reptiles, are found only in one family of mammals, the Manidce or Pangolins; but these are also associated with hairs growing from the intervals between the scales, or on the parts of the skin not covered by them. Similarly, imbricated epidermic productions form the covering of the under surface of the tail of the flying Eodents of the genus Anomalums; and flat scutes, with the edges in apposition, and not overlaid, clothe both surfaces of the tail of the Beaver, Eats, and others of the same order, and also of some Insectivores and Marsupials. The Ai-madillos alone have an ossified exoskeleton, composed of plates of true bony tissue, developed in the derm or corium, and covered with scutes of horny epidermis. Other epidermic appendages are the horns of Euminants and Ehinoceroses,—the former being elongated, tapering, hollow caps of hardened epidermis of fibrillated structure, fitting on and growing from conical projections of the frontal bone, and always arranged in pairs, while the latter are of similar structure, but solid and without any internal bony support, and (in all existino- species situated in the median line. Callosities, or bare patched covered with hardened and thickened epidermis, are found coverino- the pads under the soles of the feet and undersurfaces of the IZf.T I ^ mammals, upon the ischial tuberosities of many Apes, the sternum of Camels, on the inner side of the limbs of the ^ Galton's South Africa, jj. ] 87.