22 
The Beaver Pond at the Garden affords, perhaps, as good 
an opportunity as is possible, in confinement, of watching the 
habits of these animals, — the rough, dome-shaped structure 
of mud and sticks on the island being the far-famed Beaver 
hut, built by these animals themselves out of the natural 
materials. In a state of nature these huts are generally built 
on a small stream where the Beaver have constructed a dam, 
deepening the water sufficiently to keep it from freezing to 
the bottom, so that they can get out under the ice during the 
winter. Most of their work is done during the night, but 
towards the hour in the afternoon when they are accustomed 
to be fed they may often be seen swimming about the pond 
and disappearing with a flap of the tail as they get within 
diving distance of the entrance to the hut. 
They have done very well in their present quarters, and 
have bred there during the past summer. Their food is purely 
vegetable, consisting mostly of the bark of trees and the 
roots of aquatic plants. They formerly ranged over the whole 
of North America, but have long since been exterminated in 
the Southern, and in great part in the Middle and Eastern 
States. 
No. 5.— THE BEAR-PITS. 
But three well-marked species of Bears are believed to exist 
in North America — the Grizzly Bear ( Ursus horribilis) \ the 
Black Bear (^Ursus americanus), with its constant variety 
{cinnamoineus) \ and the Polar Bear {Ursus maritimus ') — 
though the variations of both the Grizzly and the Common 
Bear have given rise from time to time to supposed new 
species. The Grizzly ranges from the Yellowstone Valley 
and the Upper Missouri to California, and south-west into 
Mexico, — those from the western slope of the Rocky Moun- 
tains being somewhat darker in color and reaching a larger 
size than those to the eastward. 
The Black Bear is found almost all over the country, to- 
gether with what is called the Brown Bear, which is merely 
an ill-defined variety of the former species, — the black of the 
hair, in some individuals, turning to brown shortly after the 
yearly change of coat. The true Brown Bear is the Ursus 
