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THE RODENTS OR GNAWING ANIMALS. 



VciZ pocF^et flDice. 



EIGHTH FAMILY: Saccomyid^. 



Leaving the Mole Rats we may pass to the con- 

 ■sideration of a family, indigenous to North and Cen- 

 tral America, the Pocket Mice (Saccomyidcs) . This 

 division contains Rodents, possessing great diversi- 

 ties in shape, some being graceful and good-looking, 

 others again having an ungainly appearance, and all 

 being little known in respect to character and habits. 

 They dil^er from all others by the possession of 

 cheek pouches of variable length or depth, opening 

 externally and lined with fur on the inside. The 

 presence of this inner coat of fur in the cheek 

 pouches suffices to distinguish these species of the 

 order from all their relatives. The external fur of 

 the animal consists of only one wiry or stiff-haired 

 coat. 



THE POCKET MICE PROPER. 



The first and typical sub-family commonly bears 

 the name of Pocket Mice {Saccomyincz ;) their bodies 

 are slender and graceful, the hind legs are elongated, 

 the tail long and the muzzle pointed. Of this sub- 

 family the Dipodomys constitute the most promi- 

 nent variety. They bear a resemblance to the Jer- 

 boas in their outward form; the head is large, wide 

 and flat, the ears rounded, the innermost toe of each 

 foot is rudimentary but armed with a claw; the 

 tail is as long as, or longer than, the body, is fur-clad 

 and terminates in a tuft, the hind legs are distin- 

 guished by their length; the teeth contain among 

 their number rootless molars. 



Ord's Among the few varieties that have 



Pocket Mouse so far been differentiated in this spe- 

 Described. cies, Ord's Pocket Mouse {Dipodo- 

 mys philippit) is known best. Its total length is 

 about twelve inches, nearly seven of which are in- 

 cluded in the tail; the female is in length nearly an 

 inch shorter than the male. The color is similar to 

 that of the True Jerboas, head and ears, back and 

 thighs are light brown; along the under surface and 

 the flanks and crossing the thighs a stripe of white 

 extends to the root of the tail, as does another from 

 the ears to the shoulders. The tip of the tail is also 

 white; on the sides of the body the white merges 

 into a yellowish tint. 



This prettily colored and lively little creature is 

 found in California and from thence east to the 

 Rocky Mountains and south to Mexico, where it 

 lives in the most solitary and desolate regions, in 

 localities of a desert-like character, sparsely grown 

 with gigantic, wonderfully-shaped cacti. The short 

 description of its habits, which Audubon gives, 

 shows that its traits and character correspond with 

 those of the Jerboas in many respects. It emerges 

 from its hole at dusk only, and trips about amidst 

 the stones, neitl^er knowing nor fearing Man. In 

 the arid regions which compose its domain, scarcely 

 a living creature is to be found, except a great many 

 Lizards and Snakes, and hence the question often 

 arises in one's mind, how it is possible for a mam- 

 mal to exist there. Most probably Ord's Pocket 

 Mouse subsists also on seeds, roots and grasses, and 

 can go without drinking water for a considerable 

 length of time, like the Jerboas of the desert, or it 

 may be that it contents itself with the tiny dew- 

 drops which are condensed on some of the plants 

 during the night. Authoritative information as to 

 its manner of propagation and habits of life when 

 in confinement are still wanting. 



Other Species This family of Mice with cheek pouches 

 of Poohet o'' pockets situated entirely outside- their 

 J,. mouths includes several other genera, but 



mice, none which have such elongated hind limbs 



as those which characterize Ord's Pocket Mouse.' These Ro- 

 dents are called Pocket Mice, Kangaroo Rats and various 

 other local names, without much distinction of species by ordi- 

 nary observers, although science divides them into two genera, 

 each with several species. Of these Perognathus, with three 

 species, show little if any elongation of the hind limbs, the soles 

 of the paws have little hair or are bare and the fur is harsh' 

 and coarse. One species ( Perognathus penicillatus ), which 

 is found in New Mexico, Arizona and adjoining states, is about 

 the size of the Common Mouse, but has a long, tufted tail. A 

 much larger species {Perognathus fasciatus) is about the size 

 of a Chipmunk, is of more ponderous build and has a shorter, 

 tuftless tail. The third species {Perognathus hispidus) is in 

 size intermediate between the other two species and has 

 coarser hair than either of them. 



L'p it Pnrlipt ^^® third genera of this sub-family com- 

 M- "n- ■ J.- prises what have been appropriately called 

 SnTc'ies t^^ Least Pocket Mice [cricetodipus). 



" ■ These little animals are not quite two inches 



lOng, exclusive of the tail, which is of the same length as the 

 body and head together. The hind limbs are longer than the 

 fore legs, though the disparity is not so great as in Ord's 

 Pocket Mouse, but the character of their movements is such 

 that they are known in some localities as Hopping Mice. The 

 typical animal of this species is Cricetodipus flavus, which has 

 a soft, silky fur of yellowish red on the upper portion, fading 

 to a fawn colored band along the sides as a dividing hne be- 

 tween the ruddy fur of the back and the white of the under 

 portion and legs. There are other species of this group, one 

 of which is scientifically known as Cricetodipus parvus. They 

 all live in the West, from Mexico to Canada, and from the Mis- 

 sissippi river to the Pacific coast. 



An allied but little known genera of this sub-family is found 

 in the Prickly Pocket Mice {Heteromys) which are found in 

 Mexico, Central America and the West Indies, of which there 

 are several species. These are of stouter build and have spines 

 mingled with their harsh fur. 



THE GOPHERS. 



The Gophers {Geomys) show a furrow in the mid- 

 dle of their upper incisors and their ears are rudi- 

 mentary. Of the many varieties which recently 

 have been differentiated and classified, the best 

 known may serve us as a typical example. 



The Pouched The Pouched Gopher ( Geomys bursa- 

 Gopher a rius), is somewhat smaller than a 

 Type. European Hamster, being fourteen 



inches long, inclusive of the tail, which measures two 

 and one-half inches. The fur is exceedingly thick- 

 set and of a fine, soft texture, reddish on the upper 

 surface and yellowish gray below; the tail and the 

 feet, which show but a scanty covering of hair, have 

 a whitish hue. The name of Gopher is applied in 

 some American localities to various other widely 

 variant Rodents. 

 Faulty Represen- The zoologists, who first described 



tations of the the Gopher, obtained their speci- 

 Gopher. mens from Indians, who had amused 

 themselves by cramming both cheek pouches of the 

 animal full of earth, distending them to such a 

 degree that if the animal had walked the pouches 

 would have trailed on the earth. These artificially 

 distended pouches obtained for the Gopher its name; 

 the taxidermists who prepared the dead specimens 

 endeavored to give them what was supposed to be 

 a life-like appearance by following the practice of 

 the Indians ifi distending the cheek pouches, and 

 the artists who delineated the animal followed the 

 models which were accessible to them but too truly 

 in their drawings. Owing to these circumstances, 

 the pictures of Gophers of even recent date repre- 

 sent really monstrous animals, when they honestly 

 intend to familiarize us with the Gopher. 



The Gopher is distributed over the country to 

 the east of the Rocky Mountains and to the west of 



