It was because of a series of records prepared in connection with a study of the salt-water minnows that so successfully cope with the salt-marsh mosquitoes of the north (Chidester,. 1916) that the writer was invited in 1919 by the U.S. Commissioner of Fisheries, Dr H. M. Smith, to engage in an attempt at the physics and chemistry of the migrations of fish.
The subject is one that several experienced zoologists have refused to follow for any length of time, as it is difficult of field observation, and certainly not one to be solved by laboratory experiments.
After several summers of spare time spent in experimental work, amplified by field observations, it has been deemed advisable to survey the literature, and this paper will, it is hoped, aid in crystallising our knowledge of the migrations of anadromous fishes.
To a zoologist who is looking for a problem that...
