REPORT OP COMMISSIONER OP PISH AND FISHERIES. 89 



stirred until the station is reached. lie reported that the muck entirely 

 prevented adhesion, and gave no trouble whatever. After arriving- at 

 the station both lots were examined and then placed under running 

 water as usual. The current carried over nearly all of the starch and 

 a considerable portion of the muck. About twenty-four hours after 

 being taken the two lots were separately removed irom the kegs, passed 

 through a screen with meshes large enough to admit of the passage of 

 a single egg, when it was found that there were practically no lumps in 

 either case. They were then put into a screen box with mesh fine 

 enough to hold the eggs and all the muck was washed out, there being 

 no starch remaining. Examination was made of both lots with the 

 microscope, which showed minute particles of muck and starch adher- 

 ing thickly all over the outer membrane of the eggs, thus preventing 

 adhesion. Both lots showed a nearly equal percentage of good eggs, 

 the muck eggs being slightly the better. In the starch solution 11 jars 

 of eggs were taken; in the muck, 32. The muck was prepared by 

 taking black muck from the shores of a pond near by, thoroughly mix- 

 ing to a very thin solution with water, letting the vessel set about half 

 a minute to settle out the coarser and heavier particles, then decanting 

 off the water, holding the fine particles in solution, which was left to 

 settle, when the nearly clear water was poured off, the muck being then 

 rubbed through a fine wire screen, when it was ready for use. 



An experiment was also made in hatching yellow-perch eggs. The 

 eggs (73,000) were taken, April 27, from a fish weighing 9 ounces, and 

 were at once impregnated, the milt of two small males being used. 

 They were put in a McDonald jar and worked with a small amount of 

 water, being thoroughly feathered twice a day or more. Eye-specks 

 showed on the ninth day, and the fry hatched May 12. There was not 

 1 per cent of eggs in all which did not hatch. 



Experiments were made in feeding the pike perch fry to prevent 

 cannibalism. One hundred thousand fry ten days old were placed in 

 each of three kegs, each supplied with running water; one was entirely 

 darkened; the fry in the second were freely fed on graham flour, and 

 the third lot were left to themselves. The kegs were set up May 14. The 

 darkened keg was opened on the 17th and again on the 19th, and but 

 very few " doubles " were found — not over 1 per cent. The fry were 

 light colored, and not as vigorous as those which had been in the light. 

 On the 21st the keg was again opened, and a large percentage of the fry 

 being dead, the experiment was abandoned and the live ones planted. 

 There was a perceptibly greater mortality through cannibalism in the 

 keg wherein the fry were not fed than in the one where they were, but 

 it was considerable in the latter, although they seemed to eat the 

 graham flour freely and remain healthy. 



These experiments show that pike-perch fry can be held for two or 

 three weeks for the purpose of facilitating shipment by providing 

 ample tankage facilities, feeding often, and keeping the tanks moder- 

 ately dark when the fry are not feeding. 



