PROFESSOR OWEN ON THE AYE-AYE. 45 



limbs is nearly black, with a little admixture of white-tipped hairs at their thick 

 beginning. 



The tail shows no habitual twist or bend, but hangs straight from the trunk in the 

 dead animal'. It is flexible in all directions, and the long, coarse, slightly wavy hairs 

 grow equally from it all round : most are nearly black, but reflect a rufous tint in some 

 lights, through admixture of hairs that retain that colour at the base. The penis, 

 unerect, projects about an inch from the pubis ; of a subconical form, with a terminal 

 transverse orifice of the prepuce, which is of a whitish colour. The testes make shght 

 prominences below and at the sides of the penis (PI. XVI.). 



From the foregoing description we may infer that the small quadruped is arboreal, 

 the limbs being organized chiefly for grasping ; and this power is given in the greater 

 degree to the hind feet, as in all climbers. The wide circle of the ' open eye ' or fully 

 expanded eyelids, the large iris, and the pupil reducible to a minute point when the 

 iris is contracted, indicate a climber of nocturnal habits I The development of the 

 organ of hearing bespeaks the acute possession of that sense. The chief office of the 

 tail may be inferred to be that of adding to the protective non-conducting covering of 

 the body when the animal is in repose. In taking this attitude, Dr. Vinson states that 

 the Aye-aye depresses the head between the fore paws, bends over it the tail, which is 

 for that purpose depressed and curved forward ; then, slowly rolling its body into a 

 ball, covers the whole by the outspread hairs of the encircling taiP. Thus Dr. Vinson's 

 animal slept the greater part of the day, moving about and making its efibrts to escape 

 during the night. Having once succeeded, it climbed the nearest tree and moved about, 

 leaping from branch to branch with the agility of the Lemur catta ; but its ordinary life 

 in captivity suggested the idea of its being an indolent and rather slow-moving animal. 

 Its cry is a plaintive grunt*. 



§ 3. Skeleton (Pis. XIX.-XXL). 



The bones of the Aye-aye have a compact texture, and, although the specimen was 

 transmitted in spirits, they show, after a short maceration, a pure white colour. The 

 number of vertebrae between the skull and sacrum is twenty-six, of which thirteen are 

 dorsal, six lumbar, and seven cervical. The sacral vertebrae are two by anchylosis 

 and connexion with the ilia, but three by antero-posteriorly extended and co-articu- 

 lated transverse processes ; the caudal vertebrae are, accordingly, twenty-three or 

 twenty-two, — the sum-total of vertebrae being fifty-one, exclusive of the four cranial. 

 The true vertebrae describe one slight curve convex backward from the middle 



' [In the living female the tail is usually carried in a curve, concave downward. — August 1862.] 

 ^ [The pupil is widely open at dusk, when the animal is most active ; it contracts to a small circle by day, in 

 the living female. — August 1862.] 



' [The female, now in captivity, shows the same use and disposition of the tail, in repose. — August 1862.] 

 ■* Comptes Rendus de I'Acad. des Sciences, Paris, 22 Octobre, 1855. 



