REPORT OF COMMISSIONER OF FISH AND FISHERIES. LXXVH 



On April IC, near the close of the season, one of the spawn-takers, 

 Mr. Carl Rotert, was directed to remilt the eggs taken on that date; 

 that is, to add fresh milt one minnto after first applying it to the eggs, 

 and to add a third lot a minute later. In all, 450,000 eggs were treated 

 in this way, and after careful exaraiuation under the microscope, at the 

 expiration of twenty- four hours, out of the three lots of 150,000 each not 

 an unimpregnated egg could be discovered. They were then put in a 

 jar and kept thus to the close of the season. After the ruptured eggs 

 had worked off (ruptured eggs fungus and separate from the good ones 

 much sooner than the unimpregnated ones) the jar stood in striking 

 contrast to the balance of the eggs in the house, a solid mass of living 

 eggs. For some unaccountable reason they hatched before any of the 

 others, though taken last. Instead of requiring several days to hatch, 

 they all came out together, and the fry were apparently healthy, as seen 

 under the microscope or with the naked eye. It is a matter of regret 

 that this experiment was not tried earlier in the season, as it appeared 

 from the results attained in this instance that previous heavy losses on 

 X)ike-perch eggs may have been largely due to imperfect fertilization. 

 This matter will receive attention next season, and experiments will be 

 tried in remilting whitefish eggs also. 



The eggs collected at Toledo were shipped on trays by the steamers 

 running from Cleveland to Toledo three times a week, and although the 

 eggs were held at least two days on the trays, they were apparently not 

 injured by the shipment; 30,000,000 of the iDike-perch eggs were trans- 

 ferred to Cape Vincent hatchery, and in order to decide as to the best 

 method for long-distance shipments, a part of them were transferred on 

 trays, and the balance in the ordinary transportation cans filled with 

 water. Of those transferred on trays, only 30 per cent hatched, while 

 of those shipped in water 75 per cent hatched. As eggs were success- 

 fully shipped on trays from Toledo to Sandusky, it appears that the 

 loss must have been due to concussion, caused by the jolting of the cars, 

 the eggs on trays being much more subject to this than those in water. 



On May 2 it vyas observed that the eggs seemed unusually buoyant, 

 and that they rose higher in the jars than usual with the same amount 

 of water. Examination under the microscope revealed the existence 

 of numerous colonies of infusoria, nearly every egg having one or more 

 colonies. They were in the main a species of Garchesium, with a few 

 Vorticella. These being lighter than the water, and offering consider- 

 able resistance to the current, floated the eggs. On the 3d they had 

 increased to such an extent that it was necessary to put the eggs into 

 tubs and thoroughly wash them. This process broke the slender 

 threads which connect the individual infusoria to their main stem on 

 the egg, and remedied the evil. Later it was found that by thoroughly 

 feathering the eggs in the jar the same results could be secured. These 

 animals were found in all the jars, there being no difference whether 

 muck or starch had been used. Thorough investigation did not show 

 that the eggs were damaged, directly or indirectly, by these infusoria. 



