INTRODUCTION. 21
have been spared, however, to make them complete.
Fishermen have been employed for every river, to
ransack its waters by hooks and nets for possible
treasures, and to send the results of their labours for
examination and identification.
Fish, as a rule, in any stage of their existence,
are easily identified, except in some genera, where the
alteration before natural growth is complete is very
great and the immature fish is so unlike its parents
that another specific name has been actually con-
ferred upon it; while sometimes, even, the immature
fish has been placed under another generic name.
Yet the difficulty that many experienced fishermen
have in correctly naming their captures shows how
needful it is to be careful in this respect. The
resemblance of allied species, such as the Rudd and
the Roach, cause frequent mistakes. This similarity
is so strong that I rarely meet with even an
experienced angler who can give the distinguishing
characters of these common fish. Judging by the
notices in the various journals, few among our edu-
cated fishermen even appear to differentiate the
various species they capture. It may constantly be
seen recorded that so many Bream or Roach have been
taken—records perfectly useless to the naturalist, and,
from their imperfect nature, of little apparent value
to the angler or sportsman.