)ii BAIIIA BLANCA. [chap. v. 



the IJasypus minutus or pichi/, the D. villosus or pehidoj and 

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

 otner kind : a fourth species, the Mulita, does not come as far 

 south as Baliia Blanca. The four species have nearly similar 

 habits ; the j)^^udo, however, is nocturnal, while the others 

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

 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^iish woodlouse. In this state it is safe from the attack of 

 doo-s ; for the dos: not being able to take the whole in its moutli, 

 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 picl/i/ 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 Trlgono- 

 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 

 l»e in some degree independent of structure, has a tendency to 

 vary by slow degrees. The extremity of the 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 die- 



