248 MOSTLY MAMMALS 
when the river runs low. The main entrance is invariably 
placed at the end of the submerged portion, but another 
outlet may be made on shore beyond the lodge itself, and 
is then generally covered with a layer of twigs, or twigs 
and earth. As a rule, the lodges are isolated, although a 
couple may be built in contact. Seen from a distance, the 
lodge looks like a confused pile of timber and earth with- 
out any definite arrangement. The logs employed are 
usually from a couple of feet to a yard in length, although 
they may sometimes be double this size; twigs are also 
largely used, and sometimes take root and develop into 
saplings on the roofs. Stones are but seldom employed. 
Many of the logs are stripped of their bark, but others are 
built in just as they are felled; and not infrequently drift 
logs of pine and other trees which are men-felled are 
annexed. The logs and twigs are thrown together pell- 
mell, and the interstices tightly rammed with earth, the 
thickness of the walls being about a couple of feet. The 
passage leading from the submerged edge of the lodge to 
the central dwelling-chamber is usually single, and about 
twenty inches in diameter, its interior, when in clayey soil, 
becoming worn perfectly smooth. 
A double lodge opened in 1895 is described by Mr. Collett 
as follows: ‘The left or short lodge contained an unoccu- 
pied chamber without lining. The right, which was long 
and of considerable age, extended for some way under an 
oak coppice. The chamber in this was situated about six 
yards from the water, half a yard underground, and con- 
sisted of an enlargement of the passage to about three- 
quarters of a yard in height.” It was thickly lined with 
the under-bark of the aspen. 
Ice-floes and floating timber do much damage to the 
lodges, and thus entail an annual repair, which, as already 
