ALLEN : MAMMALIA : DASYPODID^. 9 



with this little Armadillo (erroneously here called Tatusia hybyida), and 

 gives the following important imformation about its distribution and habits 

 in southern Patagonia: 



" In addition to all these and many other birds and mammals, which 

 had been our daily companions ever since our arrival in Patagonia, there 

 was one curious little mammal belonging to an entirely different order, 

 representatives of which we had not met with south of the Santa Cruz 

 River. I refer to the little Armadillo, Tatusia hybrida. Frequent exam- 

 ples of these were to be seen running about over the pampa or lying 

 prone upon the ground. Immediately on touching one of these little 

 animals, they roll themselves up into a compact ball in much the same 

 manner as do some of the leeches or species of chitons, on being detached 

 from the stones to the surface of which they are usually fixed. When in 

 this position the bony covering of the carapace serves to protect them 

 from their ordinary enemies. They live in shallow holes excavated in the 

 surface of the pampa, and if by any chance they succeed in reaching the 

 mouth of one of these before being captured, they force the serrated edges 

 of the carapace into the surrounding dirt in such manner that they can be 

 extracted only with the greatest difficulty. At this latitude they hibernate 

 in winter and prefer a warm sandy soil and sheltered locality. In such 

 places they are fairly abundant north of the Santa Cruz River, but we never 

 observed a specimen south of that stream, nor after careful enquiries could 

 I discover that they had ever been seen by others in the region lying south 

 of this river. It seems probable, therefore, that this stream has afforded 

 an effective barrier to their further distribution to the southward, for not 

 only are there many localities to the south that would seem quite as well 

 adapted to their needs as those to the north, but the entire southern half 

 of the valley of that river is especially well suited to them. Though com- 

 mon in the valley on the north side of the river, no example has ever been 

 taken to my knowledge in the valley on the south side. The temperature 

 of the water in this stream, its great size, and the absolutely treeless nature 

 of the entire region through which it flows renders it particularly capable 

 of presenting an effective barrier to the free migration of certain mammals, 

 and more especially those like Tatusia, which are probably not capable of 

 swimming and are known to hibernate in winter, at which period alone 

 they would be able to cross such a stream on the ice. Their flesh is of 

 an excellent flavor and highly prized by the natives as food." 



