46 
Quadrumana.- MAMMALIA. Garkoritiiecid.?!. 
THE AYE-AYE {Cheiromys madagascariensis), fig. 
7, the only known species of this family is, as implied 
by its specific name, a native of Madagascar, where it 
was first discovered by the celebrated French traveller 
Sonnerat. The name, Aye-aye, conferred upon it by 
him is said to have been borrowed from the expressions 
of .surprise uttered by those natives to whom he showed 
Fig. 7. 
The Aye-Aye (Clieiromys Madagascariensis). 
his specimen, and who had never seen such a creature 
before ; it was, however, supposed by him to be the 
native name of his new-found treasure, and is now 
generally received as the name of the animal. 
In its general appearance the aye-aye is intermediate 
between the galagos and the squirrels, with the latter 
of which animals it is placed by those zoologists who 
refer it to the Rodentia. When adult it measures about 
eighteen inches in length, and its tail almost as much 
more. It is clothed with a thick fur composed of two 
kinds of hair; a thick woolly down close to the skin, 
and longer smooth hairs, which form the outer coat. 
The general colour of the fur is a pale rusty brown, 
with the face and throat lighter; the tail is bushy, and 
the ears very large and naked. But the most remark- 
able cbaracters of the animal we, as may be supposed 
from its doubtful position in the system, to be sought 
in its structure. The dentition, which, as a general rule, 
may be regarded as the best character by which to 
determine the systematic position of a mammal, would 
seem to indicate the justice of j)lacing the aye-aye 
amongst the rodents ; the incisor teeth, as in those 
animals, are two in number in each jaw, long, stout, 
and chisel-like, and the canines are altogether deficient; 
but the molar teeth, four in the upper and three in the 
lower jaw, although arranged in the same way as in the 
Rodentia, present certain characters which are not 
usual in that order. The skull, in its form, has some 
analogy with that of the galagos, and the bony orbits 
are complete — a character which does not occur amongst 
the rodents. 
Thus the characters to be drawn from the head and 
teeth leave the true position of the aye-aye still very 
doubtful, and it is only from the structure of 
the members that we are induced to place 
this animal with the Quadrumana. The bones 
of the forearms are distinct throughout their 
whole length, and both these and the bones 
of the wrist resemble those of the lemurine 
animals. The forehands, however, are very 
peculiar in their structure, the thumb is not 
opposable, the fingers are exceedingly long 
and thin, the fourth being the longest, and 
the third the thinnest ; all are terminated by 
large nail-like claws. In the hinder-hands, 
on the contrary, there is a distinctly^ opposable 
thumb, and the claw of the first finger is 
evidently more elongated and awl-shaped 
than those of the others, in the same way as 
in the true lemurs. Another singular char- 
acter is the position of the teats, which are 
situated on the groin. 
The aye-aye would appear to be rare even 
in its native forests; only three specimens 
have been brought to Europe, and these are 
in the museum of the Jardbi dcs Plantes at 
Paris. This rarity may, however, be due to 
the habits of the animal, which is a strictly 
nocturnal creature, sleeping during the day 
concealed in boles in the ground. It is 
described as being exceedingly sluggish, but 
we still know little or nothing of its general 
habits and food. According to Sonnerat 
it is insectivorous, and employs its long fingers in 
drawing larvae from their holes in the trees; but the 
specimens which lived for two months in his possession 
were fed with boiled rice, which they took up with 
their hands, “ using the slender fingers,” as Sonnerat 
ex[)resses it, “ in the same way that the Chinese 
employ their chop-sticks.” Other writers have sup- 
posed the aye-aye to be a frugivorous animal, and it 
must be confessed that the form of its molar teeth do 
not indicate an adaptation to an exclusively insect diet. 
Family IX.— GALEOPITIIECIDAE. 
Notwithstanding the singular characters presented 
by' the animals forming this family', the last that we 
shall refer to the order Quadrumana, their position in 
the system is by no means so puzzling as that of the 
Cheiromys ; in fact there can hardly be a doubt that 
they form a connecting link between the two contiguous 
orders of the Quadrumana and Cheiroptera, so that the 
only question is whether we shall place them with one 
or other of these orders, or, as has been done by Pro- 
