Ill THE TUCUTUCO 53 



kind of creature utters it. The noise consists in a short, but 

 not rough, nasal grunt, which is monotonously repeated about 

 four times in quick succession : ^ the name Tucutuco is given 

 in imitation of the sound. Where this animal is abundant, it 

 may be heard at all times of the day, and sometimes directly 

 beneath one's feet. When kept in a room, the tucutucos move 

 both slowly and clumsily, which appears owing to the outward 

 action of their hind legs ; and they are quite incapable, from 

 the socket of the thigh-bone not having a certain ligament, of 

 jumping even the smallest vertical height. They are very 

 stupid in making any attempt to escape ; when angry or 

 frightened they uttered the tucu-tuco. Of those I kept alive, 

 several, even the first day, became quite tame, not attempting 

 to bite or to run away ; others were a little wilder. 



The man who caught them asserted that very many are 

 invariably found blind. A specimen which I preserved in 

 spirits was in this state ; Mr. Reid considers it to be the effect 

 of inflammation in the nictitating membrane. When the animal 

 was alive I placed my finger within half an inch of its head, 

 and not the slightest notice was taken : it made its way, how- 

 ever, about the room nearly as well as the others. Considering 

 the strictly subterranean habits of the^iiisi^uco, the blindness, 

 though so common, cannot be a very serious evil ; yet it appears 

 strange that any animal should possess an organ frequently 

 subject to be injured. Lamarck would have been delighted 

 with this fact, had he known it, when speculating^ (probably 

 with more truth than usual with him) on the gx2.<^\X2\\Y- acquired 

 blindness of the Aspalax, a Gnawer living under ground, and 

 of the Proteus, a reptile living in dark caverns filled with water; 

 in both of which animals the eye is in an almost rudimentary 

 state, and is covered by a tendinous membrane and skin. In 

 the common mole the eye is extraordinarily small but perfect, 

 though many anatomists doubt whether it is connected with the 

 true optic nerve ; its vision must certainly be imperfect, though 



^ At the R. Negro, in Northern Patagonia, there is an animal of the same habits, 

 and probably a closely-allied species, but which I never saw. Its noise is different 

 from that of the Maldonado kind ; it is repeated only twice instead of three or 

 four times, and is more distinct and sonorous : when heard from a distance it so 

 closely resembles the sound made in cutting down a small tree with an axe, that I 

 have sometimes remained in doubt concerning it. 



2 Philosoph. Zoolog. torn. i. p. 242. 



