SciuRiD^. MAMMALIA. Myoxid.®. 133 
Limitation of space prevents our giving full details 
of the Marmots. Those of our readers, therefore, who 
desire further information on this head should consult 
Sir John Richardson’s “Fauna Boreali Americana,” 
where they will find a detailed account of the following- 
species of American marmots, unavoidably omitted 
in this work : — -The American Souslik {SpermopMlus 
guttatus) ; the Tawny Marmot {Arctomys Richard- 
sonii) ; the Leopard Marmot (A. Hoodii) ; Say’s Mar- 
mot {A. lateralis) ; Douglas’s Marmot {A. Douglasii ) ; 
Beech ey’s Marmot {A. Beecheyi) ; Franklin’s Marmot 
{A. FranJdinii) •, Parry’s Marmot (A. Parryi). 
In regard to the Squirrels possessing flying mem- 
branes, we can only offer the following particulars : — 
THE ETJEOPEAN FLYING SQUIRREL {Sciuropterus 
volans) is only found in the north-eastern paiis of our 
continent, being more abundant in the forests and wild 
wastes of Siberia. Its habits are similar to those of the 
common squirrel, feeding, as it does, on the buds of 
beech-trees and on the seeds contained in fir-cones. 
During its flying leaps — so much increased in power by 
membranous expansions of the skin between the fore 
and hind limbs — the tail is stretched out to aid in 
steering the body. In a state of repose, this organ is, 
as usual, gracefully curved over the back. 
NIEUHOFF’S FLYING SQUIRREL {Sciuropterus 
sagitta). — This very rare animal — concerning the spe- 
cific distinctness of which there can be no reasonable 
doubt — has been carefully described by Pennant. It 
is a native of Java and other Indian islands, and mea- 
sures eighteen inches in length, exclusive of the tail, 
which would give us other fifteen inches. The fur is 
of a bright bay colour, inclining to orange. During its. 
flying leaps, it is said to employ the tail as a prehensile 
organ. 
THE KECHUBU {Sciuropterus genibarhis) is another 
form of Javanese flying squirrel, measuring, -with the 
tail, about fourteen inches. According to Horsfield it is 
comparatively rare, and infests the forests of Pugar, one 
of the most sequestered districts of the eastern portion 
of Java. Its habits are nocturnal. The fur has a 
ta-wny-grey colour generally, the inferior parts being 
lighter ; the texture of the hah is particularly soft and 
do-wny. 
HOESFIELD’S FLYING SQUIRREL {Sciuropterus 
lepidus) very closely resembles the above, and the dis- 
tinctions given by Horsfield scarcely seem to warrant 
its being regarded as a separate species. “ It is only 
found in the closest forests of Java, where the height 
of the trees and the luxuriance of the foliage effectu- 
ally conceal it. It is with great difficulty pursued or 
seized.” 
THE GREATER FLYING SQUIRREL {Sciuropterus 
Sdbrinus)—'P\fitQ 14, fig. 43 — of North America, is 
about a foot long, including the tail. The fur has a 
pale reddish-bro-wn colour generally, being also of very 
delicate texture. The Rocky Mountain variety so 
closely resembles it, that, in the opinion of Sir John 
Richardson, the two kinds ought to be regarded as 
identical. 
THE ASSAPAN {Pteromys volucella) is a compara- 
tively small species of flying squhrel. It is very 
abundant in the United States, infesting the prairies 
in large troops. Its tail is about one-fourth shorter 
than the body, and, as in other allied forms, is flat and 
distichous. 
Family II.— MYOXIDiE. 
The Dormice represent a group intermediate between 
the squirrels and the mice. The molars are sixteen in 
number, furnished with fangs, and have their cro-wns 
marked -with transverse ridges of enamel. The feet 
are pentadactylous, but the fifth toe of the fore-foot is 
merely represented by a rudimentary tubercle or warty 
excrescence. The ears are rounded and oval, and the 
whiskers well developed. The fur is particularly soft 
and fine. The tail is very long, hairy, and more or less 
tufted at the extremity. The food of the Dormice con- 
sists principally of vegetable matters ; but they also 
devour beetles, and have been kno-wn, in a state of 
confinement, to eat bats, and even their own young. 
THE COMMON DORMOUSE {Myoxus avellanarius) 
— Plate 15, fig. 47. — This well-known little animal, 
■with its ruddy yellow fin-, is a great favourite with those 
who delight in domesticated animals — in which condi- 
tion it is particularly gentle and docile. It is tolerably 
common throughout Europe, and dwells in the seques- 
tered parts of dense thickets and plantations. During 
the summer it lays up a store against the winter, when 
it falls into a drowsy and torpid state ; but on warm 
sun-shiny days it sometimes emerges from its snug 
retreat or dormitory. Its habits are nocturnal. In 
the spring the female usually produces four young, 
which are blind at the time of birth. According to 
Mr. Bell, a second brood is occasionally brought forth 
in the early part of autumn. 
THE GREAT DORMOUSE {Myoxus Glis) is an inha- 
bitant of Southern Europe, being also found in Georgia 
and on the borders of the Wolga. It is about the size 
of our common rat, and has a pale ash-coloured fur, 
which is white underneath the belly, and at the inner 
sides of the limbs ; the eyes being surrounded by a 
dark-bro-wn circle. This animal was, in early times, 
highly prized as a dainty, and was kept by the ancients 
and fattened in separate hutches expresslj^ for the table. 
It is still eaten by the Italians. It nestles in holes of 
trees and rocks, and sometimes attacks small birds. 
Family III.— DIPODID^. 
The Jerboas are at once recognized by their re- 
markably developed hinder extremities, although this 
peculiarity is also seen in a less striking degree in the 
marsupial kangaroos. The elongation of the hind 
limbs eminently fits the members of this family for 
dwelling amongst wild wastes and open plains ; and it 
is therefore in such localities that they are found. Their 
molar teeth are complex, and in some instances desti- 
tute of roots. The hind feet are tridactylous in the true 
Jerboas, and tetradactylous in aberrant forms. The 
cla-vicles are well developed. The eyes are large ; the 
tail is very long, hairy, and frequently tufted at the tip. 
THE .EGYPTIAN JERBOA {Dipus AEgyptius ) — 
Plate 14, fig.- 45 — is extremely common in the country 
from whence its name is derived. According to Swain- 
