216 
Dasyuriixis.- 
-MAMMALIA.- 
-L)lDELPlllD-i£. 
habits are arboreo-nocturnal, and in common with its 
congeners it preys chiefly on insects and small birds. 
This species is a native of Australia generally, but has 
not, we believe, been found in Van Diemen’s Land. 
THE BANDED MYEMECOBE {Myrmecohius fuscia- 
tus) is an inhabitant of Soutli-western Australia, having 
been originally discovered and procured by Lieutenant 
Dale, at about ninety miles to the south-east of the 
mouth of the Swan Eiver. The Myrmecobe (fig. 90) 
is at once distinguished from its insectivorous con- 
geners, and also from all other marsupials, by the large 
number of teeth, of which there are fourteen incisors — 
eight above and six below — four canines, twelve pre- 
molars, and no less than twenty-four true molars ; in 
!)f). 
Tlie Biinded Myrmecobe 
all, fifty-four. The dental formula thus approaches 
very closely to that of the extinct — and probably mar- 
suiiial — genus Thylacotherium. Profe.ssor Owen also 
observes, that it is to a certain extent comparable to 
the dentition of the armadillos “ in the small size of the 
molar teeth, their separation from each other by slight 
interspaces, and their implantation in sockets, which 
are not fonned upon a well-developed ridge or process. 
The molars, however, present a distinct multicuspidate 
structure, and both the true and false ones possess two 
separate fangs as in other marsupials.” There does 
not appear to be any necessity to consider this animal 
as the type of a distinct family. It is about the size of 
a rat, measuring ten inches from the nose to the root 
of the tail. The fur exhibits a rufous ground tint 
generally, the feet being more decidedly red, the back 
dark blown and banded over the crupper by whitish 
hairs, similar to those of the thylacine. The head dis- 
jilays a sharply-acuminated muzzle and shert pointed 
ears The tail is seven inches long and bushy, the 
anterior feet pentadactylous, and the hind pair four- 
toed, all the digits being armed with strong, compressed, 
curved claws. Its habits are arboreal, and it burrows 
under the roots of trees in search of insects. 
Family VL— DIDELPIIIDvE. 
Under this head are collected together all the Ame- 
rican marsupials or opossums, properly so called. The 
species are extremely numerous, for the most part 
confined to Brazil and the neighbouring provinces of 
Guyana, Paraguay, and Peru; a few being found in 
Mexico and California, and one in the United States. 
(Jlyrmecobiiis fasciatus). 
A single species only occurs in Chili. The opossums 
are comparatively small, seldom exceeding the size of 
our domestic cat ; the jaws are furnished with eighteen 
incisors — ten above and eight below — four canines, 
and twenty-eight molars, the anterior twelve being- 
spurious (fig. 91). The head is pointed, the ears large 
Fig- 91 
Skull of tlio Virginian Opossum (Didelpliis Virgiiiiana) 
and naked, the gape of the mouth very wide, the pro- 
duced muzzle being furnished with a few long bristles. 
The tail is prehensile, more or less semi-nude or scaly. 
The feet are all pentadactylous, but the pollex of tlie 
hinder pair is opposable to the other digits, and clawless. 
The opossums are arboreal and nocturnal in their habits, 
})re}'ing chiefly upon birds, eggs, insects, and even fruit. 
Their movements, however, are rather sluggish than 
otherwise, and their presence is recognizable by the 
peculiar fetid odour of their skin. They have a simple 
stomach and moderately capacious coecum. 
THE VIRGINIAN OPOSSUM {Didelpliis Viryiniana), 
or Common Possum — Plate 30, fig. 96— enjoys the 
distinction of being the first known to naturalists. It 
