93 BAHIA BLANC A. [chap. v. 



the Dasypus minutus or pichij, the D. villosus or jjehido^ and 

 the apar. The first extends ten degrees further south than any- 

 other kind : a fourth species, the 3Iulita, does not come as far 

 south as Bahia Blanca. The four species have nearly similar 

 habits ; the peludo, however, is nocturnal, while the others 

 wander by day over the open plains, feeding on beetles, larvae, 

 roots, and even small snakes. The apar, commonly called ma- 

 taco, is remarkable by having only three moveable bands ; the 

 rest of its tesselated covering being nearly inflexible. It has the 

 power of rolling itself into a perfect sphere, like one kind of 

 Eno-lish woodlouse. In this state it is safe from the attack of 

 doo's ; for the dog not being able to take the whole in its mouth, 

 tries to bite one side, and the ball slips away. The smooth hard 

 covering of the mataco offers a better defence than the sharp 

 spines of the hedgehog. The picky prefers a very dry soil ; and 

 the sand-dunes near the coast, where for many months it can 

 never taste water, is its favourite resort : it often tries to escape 

 notice, by squatting close to the ground. In the course of a 

 day's ride, near Bahia Blanca, several were generally met with. 

 The instant one was perceived, it was necessary, in order to 

 catch it, almost to tumble off one's horse ; for in soft soil the 

 animal burrowed so quickly, that its hinder quarters would 

 almost disappear before one could alight. It seems almost a 

 pity to kill such nice little animals, for as a Gaucho said, while 

 sharpening his knife on the back of one, *' Son tan mansos'* 

 (they are so quiet). 



Of reptiles there are many kinds : one snake (a Trigono- 

 cephalus, or Cophias), from the size of the poison channel in its 

 fangs, must be very deadly. Cuvier, in opposition to some other 

 naturalists, makes this a sub-genus of the-rattlesnake, and inter- 

 mediate between it and the viper. In confirmation of this opi- 

 nion, I observed a fact, which appears to me very curious and 

 instructive, as showing how every character, even though it may 

 be in some degree independent of structure, has a tendency to 

 vary by slow degrees. The extremity of tlie tail of this snake 

 is terminated by a point, which is very slightly enlarged ; and 

 as the animal glides along, it constantly vibrates. the last inch; 

 and this part striking against the dry grass and brushwood, pro- 

 duces a rattling noise, which can be distinctly heard at the dis- 



