1 6 BULLETIN OF TEE LABORATORIES 
often used by trappers for the more expensive castoreum in preparing 
“scent” used in baiting traps. 
As, already indicated, the habits of the muskrat are subject to 
considerable variation. Its usual home is a long burrow opening be- 
neath the surface of the water and 'passing many yards into the bank, 
terminating in a cosy nest beneath the protecting roots of a tree. It 
is here that young are reared and from these burrows the entire family 
may be seen emerging at twilight to engage in swimming races, games 
of tag, and sportive contests upon the surface of the stream. The 
head and rudder-like tail alone project above the surface and the long 
V-like diverging ripples which are created by the rapid swimmer soon 
span the entire stream and stand out in bold relief as they catch the 
sky tints at sun set. In regions not frequented by man or sufficiently 
protected by trees long run-ways may be traced from these burrows 
into neighboring meadows or wheat-fields. The family is large and the 
appetite is extensive if not critical. Almost anything of a vegetable 
nature will be tolerated but the corm-like roots of rushes and the 
rhizomes of the water-lily as well as flag roots are relished. The fran- 
tic and grotesque haste with which the rat when disturbed rushes down 
the run way toward the water, oblivious to any obstacle, is very 
amusing and sometimes startling and may have given rise to the 
stories of fierce on-slaughts upon man. Young-man-afraid-of-his- 
shadow might readily consider himself beset as the excited rat comes 
crashing down his path regardless of everything but his destination. 
Nevertheless there seems to be considerable evidence that old 
“rogue” rats are decidedly irascible, and a worried mother rat may 
over-step the bounds of etiquette in defence of her young. The bur- 
rowing habits of the rat associate him with the cray-fish and other 
enemies of canals and dams. Even in the' vicinity of a large city like 
Cincinnati large numbers are annually taken in the canal-banks for 
their skins, which, when in prime condition, bring 15 to 18 cents 
The comparatively simple domicile above described is adequate 
for the southern states and flowing waters but in Wisconsin and Min- 
nesota the conditions are very different. Nearly every quarter section 
has its small lake or pond and these pools are shallow and mostly filled 
with weeds. Here the muskrat finds congeneal resorts. Even in the 
bleak prairies the sloughs and ponds fairly swarm with these furry 
denizens. Here the intense cold of winter freezes all standing water 
to a depth of over four feet so that the openings of the summer homes 
