POCKET  , a small bag, particularly a bag-like receptacle either fastened to or inserted in an

article of clothing . As a measure of capacity " pocket" is now only used for hops; it equals 168 lb . The word appears in Mid . Eng. as poket, and is taken from a Norman diminutive of O . Fr. poke, pouque, mod. poche, cf . " pouch." The form " poke " is now only used dialectically, or in such proverbial sayings as a " pig in a poke," and possibly in the " poke-bonnet," the coal-scuttle bonnet fashionable during the first part of the 19th century, and now worn by the female members of the Salvation Army; more probably the name of the bonnet is connected with " poke," to thrust forward, dig . The origin of this is obscure . Dutch has poken, gook, a dagger; Swedish pdk, a stick . POCKET-GOPHER (i.e. pouched rat), the name of a group of, chiefly North, American rat-like rodents, characterized by the possession of large cheek-pouches, the openings of which are external to the mouth; while their inner surface is lined with fur . The cheek-teeth, which comprise two pairs of premolars and three of molars in each jaw, are in the form of simple prisms of enamel, which do not develop roots . The fore and hind limbs are of approximately equal length, but the second and third front-claws are greatly enlarged, and all the claws are furnished at the base with bristles . The eyes are small, and the external ears rudimentary .

Pocket-gophers, which typify a

family, the Geomyidae, spend the whole of their time underground, and are specially organized for such a mode of existence, their powerful claws being adapted for digging, while the bristles on the toes prevent the earth from passing between them . The upper incisor teeth are employed to loosen the ground, like a fork; and the little rodents are able to move both backwards and forwards in their runs . The cheek-pouches are employed solely in carrying food, which consists largely of roots . In the typical genus Geomys the upper incisors are grooved, but in the allied Thomomys they are smooth . The common pocket-gopher, Geomys bursarius, of the Mississippi Valley measures about 8 in. in length, with a tail of between 2 and 3 in.; its colour being rufous brown and greyish beneath . A well-known representative of the second genus is Thomomys talpoides, which is considerably smaller than the former . To the farmer and the gardener pocket-gophers are an unmitigated source of annoyance . (See RODENTIA.) POCKET-MOUSE, the name of a number of small jerboa-like, chiefly North, American rodents belonging to the family Geemyidae, and constituting the genus Perognathus and Heteromys . They are nearly allied to the American kangaroo-rats (see KANGAROO-RAT), but differ in having rooted molar teeth . The typical pocket-mouse P. fasciatus, which is a native of Montana, Missouri, and Wyoming, is a sandy-coloured rodent marked with black lines above and with white beneath, and measuring about 6 in. in length, this length being equally divided between the head and body and the tail .