Eodentia. MAMMALIA. Eodentia. 
otliers call it Hudson’s Bay Leinniin^-. 'I'lie specific 
name refers to certain Rabbit-like characters. 'I’lie 
feet are densely clothed on the palms with fur, even 
in summer. In winter it is pure white. 
Fiber. — Cuvier. 
'I'liis geims was embraced in that of Castor, by 
L\ miaeus. It include.s animals that are the largest 
of the family. The form is like that of i\\& Arvi- 
eolbm. but the tail is nearly as loii" as the body, 
without the head, and it has a flattened shape, with 
no liaiiy covering, but a recticulated surface. 'I’he 
toes are incompletely webbed. 'I’lie ears are small, 
with prominent angular antitragus. The whiskers 
are short. 'L’he pelage is rather woolly in texture, 
with certain long, glossy hairs interspersed. 'I’here 
are six mammae. 'I’he perennial glands are highly de- 
veloped. 'I’he dentition is strictly arvicoline. 
MUSKRAT {Fiber zihethicus, [Lin.) Guv.) — 'I’his 
well-known animal is the only species of the genus. 
'I’he peculiarities of tail and feet separate it from 
preceding forms. 'The great size, also, is a prominent 
character. It extends over the entire continent, be- 
ing found from the Rio Crande to the Arctic regions. 
Famii.y— ZAFODID/E. 
Jumping Mice. 
'I’his family is represented by only one species. It 
was assigned to the genus Mus by older writers, and 
has been regarded as belonging to the .lerboas 
{Dipus) on account of its resemblance to the latter 
in its exterior. 'I’his family is regarded, however, as 
fully distinct, 
'The dentition is as follows : Incisors, | ; Canines, 
^-{1; Premolars, ; .Molars, f-|. 'I’he superior in- 
cisors are compi-essed and sulcate;.the premolars 
small; the molars rooted. 'I’he cranial portion of 
the skull is shorter and broader than in Muridce. 
'i’he tail is much longer than the body, very slender, 
and nearly naked. 'The locomotion is by jum])ing. 
Zapus — Coues. 
The Zapus has well-developed cheek pouches in- 
ternally. 'I’he hand has five digits, the first being 
rudimentary, with a flat, blunt nail. The palms are 
naked. 'I’he foot has five digits, with claws and webs 
at the base of each. 'I’he pelage is coarse and harsh. 
JUMPING MOUSE ; DEER MOUSE {Zapus hudson- 
im, Coues). — 'I’his odd little creature was first 
brought to notice by Pennant as the “ Long-legged 
Mouse of Hudson’s Bay,” or a similar name. Under 
the head of Deer .Mouse {Meriones ainericanus), De- 
Kay describes this species. He says that it is com- 
mon in all parts of New York State. 'I’he Indians 
called it Wuli-peh-sous, or the animal that “jumps 
like a deer.” It is said to leap ten or twelve feet at 
a bound. 
Family— S ACCOM YIDyE. 
'I’his family is recognized in the peculiar character 
of external cheek pouches, which are lined with a 
furry integument, and open outside of the mouth. A 
general murine aspect is also seen in the individuals. 
'The oidy other' Rodents that possess the external 
jjouches are the Oeomyidm which are entirely diff'er- 
ent in external aspect. 'I’he family name is derived 
from the Latin saccus, a bag. 'I’he skull is light, 
thin and papery. 'The mastoid processes are enor- 
mously enlarged, reaching to the top of the skull. 
'I'lie hind limbs are formed for jumping. 'The tail is 
as long as the body. 'I’he pelage is coarse and harsh, 
said to be mixed with flattened spines in some in- 
stances. 'I’here is no under fur. 'I’lie species are 
very active, resembling Mice in their movements, oc- 
casionally leaping like the Jerboas. 
Sub-Family— PEROGNATHIDINH51.— Comc«. 
'I’liis sub-family was instituted by Coues. R has, 
among other characters, rooted molars ; compressed 
and silicate upper incisors; an inflated temporal 
region (moderate as compared with others) ; and a 
comparatively hispid pelage. 
Perognatiius. —Max. 
'I'lie upper incisor.s in this genus are small and 
compressed, inclining backwards. 'I’heir faces are 
dee|)ly channeled with a longitudinal groove. 'I’lie 
under incisors are small and simple. 
BANDED PEROGNATHUS {P. fasciatus. Max.)— 
'This is the largest of the genus. Its length is about 
four inches ; the tail somewhat less. 'I’lie ears are 
large. 'I’lie soles are naked to the heels. 'The color 
above is reddish-yellow, closely lined with black- 
ish. It inhabits the country between the Missis- 
sippi and the Rocky Mountains, and the northern 
portion of Mexico. 'I’he pelage of this species is 
harsh, and is likened to spun glass of a very delicate 
nature. 
TUFT-TAILED POCKET MOUSE {P. penicillatus, 
Woodh .) — About the size of Hesperomys leucopus. 
It is a rare animal, found in the Basin of the Colora- 
do River. 
MOUNTAIN POCKET MOUSE {P. monticola. Baird). 
— About the size of Mus musculus. 'I’lie tail of this 
species is quite a distinguishing feature, measuring, 
including the hairs, an inch longer than the head 
and body. 'I’he pelage is very soft and smooth for 
the genus. Color above, yellowish-ciiinamon, lined 
with blackish ; below, white. Its length is two and 
a half inches. It inhabits the western slope of 
Rocky Mountains, Utah and California. 
HISPID POCKET MOUSE {P. hispidus, Baird).— 
'J'liis is about three inches long; the tail a little 
more. It is very rare. Coues speaks of only two 
species being known, these being from Mexico. “'I’lie 
fur is exceedingly stiff and coarse; the ear small, 
concealed in the fur. The soles are naked. 'I’lie 
color above is yellowish-cinnamon, closely lined with 
blackish, the color not descending on the leg. 'I’lie 
sides have a conspicuous fulvous stripe. 'I’he tail is 
bicolor. 'I’he under parts are white.” 
HONDURAS POCKET MOUSE {P. hicolor. Gray) is 
a species from the Isthmus. “ It is dark brown 
above — not black — with harsh pelage.” 
