The vizcacha appears to be a rather common species over all the extensive Argentine territory; but they are so exceedingly abundant on the pampas inhabited by man, and comparatively so rare in the desert places I have been in, that I was at first much surprised at finding them so unequally distributed. I have also mentioned that the vizcacha is a tame familiar creature. This is in the pastoral districts, where they are never disturbed; but in wild regions, where he is scarce, he is exceedingly wary, coming forth long after dark, and plunging into his burrow on the slightest alarm, so that it is a rare thing to get a sight of him. The reason is evident enough; in desert regions the vizcacha has several deadly enemies in the larger rapacious mammals. Of these the puma or lion (Felis concolor) is the most numerous, as it is also the swiftest, most subtle, and most voracious; for, as regards these traits, the jaguar (F. onca) is an inferior animal. To the insatiable bloody appetite of this creature nothing comes amiss; he takes the male ostrich by surprise, and slays that wariest of wild things on his nest; He captures little birds with the dexterity of a cat, and hunts for diurnal armadillos; he comes unawares upon the deer and huanaco, and, springing like lightning on them, dislocates their necks before their bodies touch the earth. Often after he has thus slain them, he leaves their bodies untouched for the Polyborus and vulture to feast on, so great a delight does he take in destroying life. The vizcacha falls an easy victim to this subtle creature; and it is not to be wondered at that it becomes wild to excess, and rare in regions hunted over by such an enemy, even when all other conditions are favourable to its increase. But as soon as these wild regions are settled by man the pumas are exterminated, and the sole remaining foe of the vizcacha is the fox, comparatively an insignificant one.