THE LIVING WORLD. 
505 
The Brazilian Tree Porcupine ( Sphiggums prehensilis) is sixteen to twenty 
inches long to the base of the tail, the latter nearly as much more. It is abun¬ 
dant in Guiana, Brazil and Bolivia, and feeds on the fruit of the palms. 
The Mexican Tree Porcupine ( Sphiggums mexicanus) is mostly black; 
the spines are nearly all hidden by the fur, yellowish or whitish with black 
points; it is about eighteen inches long, its tail about fourteen; it inhabits the 
temperate mountain regions of eastern Mexico, between 2000 and 4000 feet 
above the sea. 
The Ground Pig, or Ground Rat ( Aulocodus swinderianus) , is a beaver- 
porcupine diminutive in size, found in South America and chiefly interesting 
because fossil bones of the same species have been discovered in the Eocene strata. 
The Cuypu ( Myopotamus coypu) inhabits the banks of a great many South 
American streams, and is found on both sides of the Andes. On the eastern 
side its habitat extends from Peru to 43 0 south latitude, on the west from 
Central Chili to Terra del Fuego. It is found also along the bays and channels 
between the little islands of the Chonos Archipelago. The specie peculiar to 
river-banks, subsist on vegetable matter, while it is said that those found near 
the sea add shell-fish to their bill of fare. It has the size and general appearance 
of a beaver, in fact it is sometimes called the La Plata beaver. Its general color 
is a dusky brownish-yellow. The hair is fine and silky, and at its base is a 
fur similar to that of the beaver, which has become a considerable article of 
commerce. The animal is nocturnal and is hunted only at night with dogs, 
with which it fights ferociously. Its flesh is white and agreeably flavored, 
though it is not generally eaten. Buenos Ayres is the headquarters of the trade 
in this sort of fur. 
The Viscacha, or Biscacha {Lagostomus trichodactylus) , is somewhat like the 
rabbit. It has smaller but wider-spreading ears ; its tail is about one-fourth of the 
length of the body and its tip turns upward. Its fur is close and fine, brownish- 
gray above and shading into white below. It flourishes on the pampas of 
Buenos Ayres. Here they are eagerly hunted and promptly put to death, not 
because their flesh is good for food, but because they dig up the soil and damage 
the crops. They serve one useful purpose after death, since their fur is made 
into caps. They live in companies, seldom venture far from home, are vegetarian 
in diet, move by leaps, like to pose upon their haunches, and carry food to 
their mouths with their fore paws very much as squirrels do. They express 
their feelings by a variety of short cries. The female produces four or five 
at a birth. The favorite resort of the viscacha is that part of the plains which 
during one-half of the year is covered with immense thistles, to the almost 
entire exclusion of other plants. Like the magpie, the viscacha carries off objects 
for which it has no possible use. Every hard object it finds, it drags forward 
to the mouth of its burrow, but for what purpose no one knows, as it does not use 
them as weapons of either attack or defence. One dark night, as he was riding 
along, a traveller dropped his watch. Missing it at his journey’s end, he retraced 
his steps the next morning, examining the entrance of each viscacha burrow on 
his route, when at one of these lay the lost property. 
Cuvier’s Lagotis, or the Alpine Chinchilla ( Lagidium cavieri ), resembles 
the viscacha, and is itself sometimes called by that name, yet its body is more 
slender, the thickest part being near the tail; the ears are longer and stand straight 
up from its head, and the tail is long and carried straight out. The body above 
