Text book of zoology / by J.E.V. Boas ; translated by J.W. Kirkaldy and E.C. Pollard.

Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: Text book of zoology / by J.E.V. Boas ; translated by J.W. Kirkaldy and E.C. Pollard. 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.

    552/584 (page 530)
    occurs in Britain, and is widely distributed over tiie Continent. Several other species are met with in soutlieru, or southern and eastern Europe: the Squirrel- tailed Dormouse {M. glis), the largest species: the Garden Dormouse {M. nitela): the Tree Dormouse {M. dryan). Allied is the Sminthu^ betuKnus or vuf/as, in Noi-th and East Europe, very like a Mouse extenially. witli m |. The Sminthus is closely allied to the Jerboa (Diiyiix), which is chiefly characterised by the great length of the hind foot; tliis especially affects the second to the fourth metatarsals, which are fused (the first to the fifth toes are small or absent); the animals hop ahmg, stepping only upon the second, third, and fourth toes of the hind foot; the tail is long, -vvith a tuft of hairs at the end : desert animals; South Russia, Asia, Africa. Also allied to the Sminthus is the blind, earless, and tailless Mole-rat (Spalax typhhta), -whone habits are some- what similar to those of the Mole; South-East Europe (e.g.. South Russia) and Western Asia. 4. M o u s e F a m i 1 y (Miiridu;). M (occasionally ^, cf., p. .528); very varied in structure; tail longer or shorter, scaly ; pollex rudimentary. Usually of small size. (a) Rats and Mice (MiLt). Molars tubei-culate, Avith shoi-t cro-ivns and with roots ; tail long, slightly hauy; puinaj fairly well developed. In England occur: the Wood Moiise, or Long-tailed Field Mouse (M. sylvaticus), tind the Harvest Mouse (M. minutus) -. the following have invaded and live in human dwellings: the House Moiise {M. niunculus). the Black Rat (M. rattiis), now rare, having been almost completely exterminated by the more recent immigrant, the Brown Rat {M. decumanus). Allied to the Mice is the brightly-coloured Hamster {Cricetus frumentarius), with cheek pouches and short tail; somewhat larger than a Rat: Central Eui'ope. (&) Field Mice (Arvicola). Molars long, growing from persistent pulps, with deep grooves on each side (gTindiug surface with loops of enamel); occasion- ally there are short roots; tail shorter and more hairy than in the Mice; pinna' shoi-t. They buiTow in the ground, and are more exclusively herbivorous (feeding upon roots, bark, etc.) than the true Mice. The following species occur in England: the Bank-vole (.4. f/Z« reoZa), which affords a transition to true Mice ; the molars with short roots; pinna! and tail somewhat longer than in the rest: the Field Mouse (A. agrestia and ai-valis): the Water Rat (A. amphibius); the latter is the size of a Brown Rat, the others about as large as the House Mice. Closely allied is the Lemming (Myodes lemtnus), with very short tail, and strong claws on the fore limbs ; Scandinavia : famed on accoimt of its migrations. Another foi-m allied to the Field Mice is the Musquash or Musk Rat (Fiber zibethicus), with long, compressed tail; the toes with stili' hairs at the edges; furry animals of fairly large size, inhabiting northern North America, and by their mode of life recalling the Beaver. 5. Hystricomorpha, a group consisting of numerous forms, differing very much externally, but agreeing chiefly in the characteristics of the skull.* Molars [ . banded, with roots, or growing from persistent pulps. («) The Coypu [Myopoiamus coypu). an aquatic animal of beaver-like appearance, but smaller, and with a rounded tail; the toes of the hind foot are webbed; South America. (b) Porcupines (Hystricidw), chamcterised b}^ the modification of some of the hairs into stiff spines, often of enormous thickness and cousider,ible length; animals of considerable size. The Common Porcupine (Hy.stri.>- cristata), in South Europe ; lives in holes in the gi-ound; tail short. In America, there are various arboreal forms, (Cercolabes) with prehensile tiiils. * E.g., the infraorbital foramen is huge, and tlic iiiiuidibli- is ]>o( uliar in form.