PIKES AND PIKE PERCH 15 
used with success, and experiments with starch also have given good 
results. In each case the action is entirely mechanical. Having 
been found effective, cornstarch probably is more generally resorted 
to than any other substance, and most fish-culturists find it satisfac- 
tory and readily obtainable. Silt or swamp muck is strongly recom- 
mended for this purpose by the superintendent of the bureau’s Put 
in Bay (Ohio) station. The following is his description of the 
method employed by him in its preparation and use: 
In the spring of 1895 finely divided, washed, and screened swamp muck was 
tried at Put in Bay and has been used ever since, and recently with complete 
success, Owing to a change in the method of application. The plan pursued 
up to 1899 was to add muck to the water in the kegs into which the eggs were 
poured after impregnation, and to wash them quickly. The washing was done 
quickly in order to prevent cohesion. This was effective, but it involved the 
use of too much muck, which was removed from the water with some difficulty 
and which smothered the eggs if left in too long in any quantity. Further- 
more, it was difficult to get exactly the right quantity of the mixture. Careful 
experiments were therefore made in using the muck in the pan immediately 
after impregnation had taken place, and satisfactory results were obtained. 
At the present time the eggs are allowed to stand in the milt for about 10 
minutes, with sufficient water barely to cover them, and are carefully stirred 
once or twice in the meantime. Then a tablespoonful of the muck mixture, 
of the consistency of thick cream, is added. Next the pan is nearly filled with 
water and the contents thoroughly stirred. It is then allowed to remain un- 
disturbed for half an hour while another pan is being filled. Without moving 
pan No. 1 more than is necessary, the surplus water is poured off, the pan 
again filled, stirred, and left as before, while pan No, 2 is treated like the 
first. If the boat rocks so as to endanger the safety of the eggs it is better 
to pour them carefully into the keg and let them stand there, keeping only 
about an inch of water over them and pouring the water off and adding fresh 
water at intervals of not more than half an hour. 
The important thing in preventing cohesion is to leave the eggs undisturbed 
until the particles of muck or the spermatozoa, in case the eggs are held in 
the milt without the addition of muck, have settled. The comparatively clear 
water is then poured off and a fresh supply added, at which time the eggs 
are gently agitated. It will be observed that most of the muck particles will 
have settled in one minute, the water becoming measurably clear. If the eggs 
are held in the milt, the water being very milky from the mixture, the water 
will become comparatively clear in three or four minutes. This is because 
the spermatozoa are slightly heavier than the water and settle to the bottom. 
In either case it is important to retain the particles in the remaining water 
and eggs until cohesion has ceased, in order to keep the eggs separated, for 
although the particles of muck or the spermatozoa, as the case may be, are 
adherent, sticking to the surface of the egg, they are easily washed off, thus 
permitting the eggs to come into contact and become fastened together. Aside 
from the washing off, the area of the egg membrane becomes constantly 
greater, removing the particles farther and farther from each other until 
finally the surfaces meet and cohesion takes place. This will not occur if the 
muck particles or the milt are left until cohesion has ceased or until the egg 
has become virtually filled with water—that is, has finished swelling. 
While the eggs are soft and not cushioned by the absorption of water, the 
greatest care possible will not prevent the rupture of a considerable percentage 
of the sacs where the old method of constant working to prevent cohesion is 
pursued. By holding the eggs in the milt—which is better than the old way 
and requires less labor, but is not to be compared with the muck process—or 
by using muck, with reasonable care in all other directions, the loss may be 
measurably reduced. 
The preparation of the muck solution is very simple, but should be carefully 
conducted, as follows: 
At a suitable place in a swamp a depression is dug, which quickly fills with 
water. Muck is now suspended in this water by thorough beating and stirring 
until most of the muck particles are freely divided. Care is taken not to get 
