muddy, partly gravelly, supporting a dense growth of aquatic
vegetation. The brook has two clean lakes at its source, and its water
is purer than that of ordinary brooks.

The collection of salmon usually continues from the first ten days of
June until the beginning of July. During the early weeks of their
imprisonment the salmon are extremely active, swimming about and
leaping often into the air. After that they become very quiet, lying in
the deepest holes and rarely showing themselves. Early in October they
begin to renew their activity, evidently excited by the reproductive
functions. Preparations are now made for catching them by constructing
traps at the upper barrier. If the brook is in ordinary volume, these
means suffice to take nearly all, but a few linger in the deeper pools
and must be swept out with seines. About October 25 the taking of spawn
begins. After that date the fish are almost always ripe when they first
come to hand, and in three weeks the work of spawning is substantially
finished.

Although the salmon are taken from the fisherman without any attempt to
distinguish between males and females, it is always found at the
spawning season that the females are in excess, the average of four
seasons being about 34 males to 66 females. This is a favorable
circumstance, since the milt of a single male is fully equal to the
impregnation of the ova of many females.

The experiment has several times been tried of marking the salmon after
spawning and watching for their return in after years. After some
experiments, the mode finally fixed upon as best was to attach a light
platinum tag to the rear margin of the dorsal fin by means of a fine
platinum wire. The tags were rolled very thin, cut about half an inch