FEEDING AND REARING FISHES. 
305 
iu view of these highly estimable qualities, ami because it can bo given to trout without any mechan- 
ical preparation, even to the, smallest. Some 20,000 or 30,000 pounds a year are collected. * * * itg 
onlj" defect is that it keeps but for a short time. It rots, and is devoured rapidly by other insects 
developed in it. 
Ill the same letter it is stated that rainbow trout at 1 year old, fed on Goriza, 
attain a weight of 160 pounds per 1,000 lish. I know of no other place where 
attention is given to the Goriza except the Neosho Station, where it is not used for 
the trout but for the pond fishes, black bass, rock bass, etc. 
Last year Mr. A. N. Cheney called attention to the methods of the Austrian, Carl 
Elder von Scheidlin, who says: * “I, by fidlowing further on the lines of the French- 
man, Liigrin, have solved” the question of jiroper food, “ and have tested the solution 
as good, cheap, and practically feasible.” Mr. von Scheidlin has proiiosed, through 
Mr. Cheney, to make over his method of rearing natural food for use in the United 
States, and correspondence is now going on to that end. 
Up to the present time the only tangible effort of a European in the direction of 
cultivating natural food for fishes which the American fish-cuiturist can take hold of 
has not been accomplished by a lish-ciiltiirist, but is the result of investigations and 
experiments conducted by Dr. W. Kochs, of the University of Bonn, on the Artificial 
Propagation of Minute Crustaceans. The results of this work appeared in Biolog- 
isches Centralblatt, October, 1892, and on account of its exceeding value a full trans- 
lation is offered on pp. 306-308 of this paper. Occasion is taken to recommend for con- 
sideration, particularly of the pond ciilturist, the suggestion of Dr. Kochs to construct 
insect-breeding ditches along the banks of the ponds, from which the infusoria and 
Crustacea may find their way into the ponds. Observation has fully convinced me of 
the value of the hint given by Dr. Kochs of the fondness exhibited by Gammarm for 
dry brushwood, and I might state that the same seems true of all woods in which 
decay has commenced; Goriza in particular seems to frequent lialf- rotted logs lying in 
warm, shallow water, though I believe Oammarus prefers clean running streams. I 
have found it most abundant in water of a temperature not unpleasant for drinking. 
Translations of portions of reports by M. Chabot-Karlen on the fish-cultural 
operations of MM. Durand, Binder, Despres, and other culturists of France are sub- 
mitted on pp. 309-311. I would invite attention particularly to M. Durand’s method 
of propagating the GycJops^ and I am prepared, from my own observations, to unquali- 
fiedly indorse his remarks as to the value of Potamorjeton nnd Nastirrtinm as a shelter 
for tlie smaller Crustacea. 
As before intimated, little or no systematic attention, except on an experimental 
scale, has been given this subject by American fish-cultnrists; the only approach to 
the European method f)f which I am aware being that at the private ponds of Mr. 
Fairbank, of Illinois, and even there the effort is like that of Mr. Andrews. 
One of the objections which has been raised to the employment of natural food 
is the time and expense which would be involved in collecting enough for feeding a 
large number of fish. To this I make answer: First, be certain how much food jmu 
need to produce the best results. A comparison of the values of different foods as 
determined by chemical analysis and as exhibited on i>age 295 will show that from 7 to 
10 pounds of the artificial food may well be replaced by 1 pound of natural food. I 
say well replaced, because if 1 pound will do the work why burden the system with 
the useless 9 pounds ! 
* U. S. Fish Commission Bulletin, 1893, p. 278. 
F. C. B. 1894—20 
