42 PATAGONIAN EXPEDITIONS : ZOOLOGY. 



Mr. Hatcher gives a somewhat extended account of the Tuco-tuco, which 

 apparently refers mainly to the present species. The locality is the vicinity 

 of the junction of the Rio Belgrano with the Rio Chico. He says (Narra- 

 tive, pp. 124, 125): 



"All about us, and indeed at times from immediately beneath our feet, 

 could be heard the deep, subterranean drummings of the little tuco-tuco, 

 Ctenomys tnagel/aiiica, as engaged with commendable industry, he drove 

 his little tunnel just beneath the surface, ever onward in search of those 

 nutritious roots and succulent tubers upon which he feeds. These little 

 fossorial rodents seemed especially active in the early morning and late 

 afternoon and evening, During these hours, in localities especially favor- 

 able to them, they would be constantly heard, though a careful watch 

 throughout our stay in Patagonia, kept at frequent intervals in order to 

 observe their habits above ground, was only rewarded by a momentary 

 glimpse, on one or two occasions, of a solitary individual, as he appeared 

 for an instant at the mouth of a burrow. On one occasion, however, 

 while walking rapidly along, I came suddenly upon one of these little 

 animals in the grass at a distance of several feet from the mouth of his 

 burrow; The manner in which he ran aimlessly about in search of his 

 hole, with the nose close to the surface of the ground, seemed to indicate, 

 not only that he had lost his way and become bewildered by the grass, 

 which, to him, had all the appearances of a great forest, but that he depended 

 quite as much, if not more, upon his sense of smell as that of sight, while 

 endeavoring to regain the abandoned burrow. Hardly had he entered 

 the latter when the frightened condition under which he had been so 

 evidently laboring w^hile above ground, suddenly and completely disap- 

 peared, and he stopped long enough to send back a rapid volley of deep, 

 guttural notes, uttered in defiance at the intruder, who, far from having 

 cherished any sinister designs against the little creature, had only been 

 delighted with this opportunity, brief though it was, of observing him above 

 ground. The entire attitude of the little animal was such as to convince 

 me that his surroundings while above ground, aside from my presence, 

 were distinctly uncongenial, and that he was in every respect especially 

 modified and adapted for a subterranean life, a conclusion which I had 

 previously reached upon observing the small eyes, powerful fore-limbs, 

 and feet well adapted for burrowing, and other anatomical characters 

 common to animals of more or less subterranean habits." 



