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 : 1 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 tucutuco, 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 2 (probably 
with more truth than usual with him) on the 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 
1 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. tom. i. p. 242. 
