558 NATURAL HISTORY. 
of the east. This was the largest we ever saw, nor have I 
ever heard of one as extensive. For three days we travelled 
through this colony, during which time we did not lose sight 
of them. On either side, as far as we could see over the plain, 
their habitations extended, standing out in bold relief in the 
little hillocks they had raised with the earth brought from 
their subterranean abodes. Their habitations are usually 
about ten yards apart, and the hillocks contain from one to 
two cartloads of earth each. Some have one entrance, others 
two, which incline at an angle of about forty-five degrees, 
To what depth they extend I could never Jearn, and only 
know that the frequent attempts to drown the animals out by 
pouring large quantities of water in them, have rarely suc- 
ceeded.* 
A well-beaten track extends from one to the other of these 
hillocks, showing that a close intimacy exists between their 
occupants, or perhaps family connection. We supposed this 
community or ‘*‘ dog-town,” as it is called, extended at least 
sixty miles, as we travelled at that time twenty miles a day, 
As to its width, we could not form a decided opinion ; but 
presuming it to have been only half as wide as it was long, an 
idea may be formed of the vast number of animals it con- 
tains. 
For the greater part of this distance the country was flat, 
and covered with short grass, kept so probably by these ani- 
* Lieutenant Abert mentions an instance where several were obtained by 
pouring water into their burrows. They afterwards became quite tame.— 
Report, p. 421. 
+ If we suppose that this community extended fifty miles in one direction 
and but ten in another, we have a superficies of five hundred square miles; 
and allowing them to be thirty feet apart, or nine hundred square feet for 
each (a large allowance), it would give about thirty thousand habitations to 
the square mile, or 15,000,000 in the five hundred miles. Estimating but two 
of these little creatures, which is the smallest supposable number to a habita- 
tion, we have a total of thirty millions in this community. I think it would be 
quite safe to reckon three or perhaps four animals to each hillock. 
