492 ZOOLOGY. 



These extremities are also concerned in locomotion. Quadrumana therefore 

 have four hand-like feet ; the distinction between the anterior and posterior 

 extremities, so remarkable in man, does not strike us here, except to a very 

 slight degree. These animals climb trees with facility, or may walk on 

 their four limbs, in which case the foot rests only on its outer edge. 

 Sometimes they may stand upright, but this they always accomplish with 

 difficulty. 



Quadrumana may be conveniently divided into two groups : the monkeys 

 {Simice) and the lemurs or makis {Prosimice), the latter being preceded or 

 followed by two genera whose strange combination of characters has thrown 

 a certain obscurity upon their true affinities. 



Fam. 1. C111ROMYID.E. The genus Chiromys or aye-aye of Madagascar 

 is the only one which composes this family, and is placed by some among 

 Rodentia. This animal is rare even in its native country. In its general 

 conformation it is strictly lemurine, though having much of the aspect of a 

 squirrel. The extremities have five fingers ; the first is separated from the 

 rest, and shorter, so as clearly to represent the thumb, although the latter 

 is not opposable. The first toe is armed with a straight, pointed claw, as in 

 the lemur. Its habits are those of the lemurs, being concealed most of the 

 time during the day in some hollow, and sleeping. At night it issues forth 

 in search of its food, which consists of buds and fruits, with insects and 

 larvJB. The tail is long, and always kept trailing. Each jaw has only two 

 front teeth, very large, strong, flattened, and their roots extend backwards 

 along almost the whole length of the jaw ; between these and the molars 

 there is a wide interval, as in the rodents. The molars, however, are sim- 

 ple in their structure. There are two mammae situated near the groin, as 

 in Rodentia, but again, in the tarsiers, we find two pairs of them, one 

 pair on the chest, the other in the groin. Only one species is known {C. 

 psylodactylus)^ the a3^e-aye. 



Fam. 2. Galeopithecid^. This family, like the preceding, is composed 

 of a single genus, the genus Galeopithecus, or flying lemur, a native of the 

 Moluccas, Philippines, and other islands of the Indian Archipelago. Its 

 chief peculiarity consists in the extension of its skin between the anterior 

 and posterior limbs on each side, and also between the two posterior limbs, 

 including the tail, so as to form a parachute of considerable extent, which, 

 though it does not enable the animal to fly, gives it support in the air 

 sufficient to enable it to take long sweeping leaps from tree to tree with the 

 utmost facility. The extraordinary combination of characters exhibited by 

 this animal has puzzled the naturalists as to the place which it should occupy 

 in the series of beings. The general aspect of the head is lemurine ; the 

 extremities are all furnished with five fingers, but the first or the thumb is 

 separated from the rest, and does not antagonize with them, being short, 

 whilst the remaining ones are nearly equal, and armed with large, deep, 

 hooked, sharp-edged, retractile claws, resembling those of the cat tribe. 

 There are four incisors in each jaw ; the canines are absent in the lower; 

 the molars are six on either side in each jaw, and are raised up into 

 pointed tubercles. During the day, these animals remain in the depth of 

 690 



