A REMARKABLE MAMMAL 183 
which can be drawn across them from one side. The 
large and rounded ears, which are inclined backwards, 
are naked and dotted with a number of small tubercles. 
The blackish brown hair all over the body is long and 
coarse, but becomes longer still on the long and bushy 
tail. Nothing very remarkable exists in the structure of 
the hind-limbs, which somewhat exceed the front pair in 
length ; but the forepaws, or hands, which are unusually 
elongated, display a most strange peculiarity. As in lemurs 
generally, the thumb is capable of being opposed to the 
index finger, which is short; the latter, together with 
the fourth and fifth digits, being of normal thickness and 
provided with long compressed and pointed claws. The 
third or middle finger, as is beautifully shown in the 
figure, is, however, quite unlike the others, being extremely 
thin and spider-like. Of its use, mention will be made 
later. 
This attenuated middle finger is one of two marked 
peculiarities whereby the aye-aye differs so strangely from 
its relatives the lemurs. Its other peculiarity is to be 
found in its.dentition. Ordinary lemurs, it may be observed, 
have from thirty-two to thirty-six teeth; the incisor or front 
teeth, although presenting certain peculiarities of form, 
agreeing numerically with those of monkeys and man in most 
cases. In the aye-aye, however, there are only eighteen 
teeth, all told; the incisors being reduced to a single pair in 
each jaw, the canines, or tusks, wanting, and the cheek-teeth, 
or grinders, comprising four pairs in the upper and three 
in the lower jaw. Nor is this all, for the incisors, which 
grow throughout life, are large somewhat chisel-like 
teeth, recalling in many respects those of a beaver or 
other rodent, although with peculiarities of their own 
which render them easily distinguishable from those of all 
