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constructed in a particular way—the result being that the 
opening is a very considerable one ; often four to six feet 
across the mouth, and sometimes deep enough for a tall 
man to stand up waist-deep in. 
The next point to be observed is that the vizcachera 
is the centre of a clear space, often of half an acre in 
extent, on which there is an even, closely-shaven turf. 
This clearing is surrounded by the usual rough growth 
of herbs and giant grasses. And now we come to the 
senseless, useless act, of which Mr. Hudson says :— 
“Another remarkable habit of the vizcacha—that of drag 
ging to and heaping about the mouth of his burrow 
every stalk he cuts down and every portable object that 
by dint of great strength he can carry—has been men 
tioned by Azara, Darwin and others.” 
All these arrangements are of the highest utility, and 
we are justified in supposing that even if they are some 
times instinctively performed now, they had their origin 
in intelligent purpose. 
In the first place, the manner of burrowing is of great 
advantage, because, on the perfectly level and shelterless 
pampas, the durability of the burrow—a circumstance 
favourable to the animal’s preservation—is owing alto 
gether to its being made in a certain way, and to several 
burrows being made together. The two outer trenches 
diverge so widely from the mouth that half the earth 
brought out is cast behind instead of before it, thus creat 
ing a mound of equal height about the entrance, by which 
it is secured from water during great rainfalls, while the 
cattle avoid treading over the great pit-like entrances. 
But the burrows of the dolichotis, the armadillo, and other 
species, when made on perfectly level ground, are soon 
trodden on and broken in by cattle; in summer they are 
choked up with dust and rubbish ; and the loose earth