LXXII REPORT OF COMMISSIONER OF PISH AND FISHERIES. 



and put them in the supplemental nets, and also to collect the eggs 

 from ripe females. The dip nets used for taking the fish from the pounds 

 have long handles and hoops of spring steel, and are covered with 

 heavy open cloth such as is used in the cider press, as the knots and 

 twines of the ordinary net would injure the scales of the fish. 



The steamer visited the supplemental nets daily when the weather 

 permitted, and removed the lish to spacious tanks on board, then 

 transferring them to the station, where they were counted and assorted. 

 It is necessary to exercise much care in this work, as success is entirely 

 dependent upon the fish reaching the live-boxes uninjured. Before 

 placing them in the boxes they are assorted into three classes — soft, 

 medium, and hard. The soft ones (those nearly ripe) are examined 

 each day; the medium every third or fourth day, and the hard ones 

 at the end of each week. In this way much unnecessary handling is 

 avoided and the fish are kept in good condition. At the close of the 

 season all were returned to the fishermen in excellent condition. 



Spawn taking is conducted under a temporary shelter erected on a 

 raft, and does not differ materially from the mode generally pursued. 

 The last fish were removed from the live-boxes on December 13, 

 when six of them were placed in one of the fry-tanks at the station for 

 future experiment. One of these was what is known as a "plugged" 

 female; that is, her abdomen remained hard and showed a congested 

 condition. This specimen was killed and opened. The ovaries were 

 found to be congested and the eggs, when examined under the micro- 

 scope, all showed ruptured yolks. Two of the other fish were appar- 

 ently healthy females containing spawn, and two were healthy males. 

 These were held in the fry tanks until December 21, when the females 

 were found to be ripe. In fact, one of them had cast most of her eggs 

 in the tank. From the other nearly a quart of spawn was taken. 



The eggs were fertilized with milt from one of the males and presented 

 a very good appearance, though it was noticed that they were a little 

 undersized, ruuning 10 to the linear inch instead of 8. The tempera- 

 ture of the water at the time being 32.5°, the eggs did not show dis- 

 tinct segmentation at the end of the first 21 hours, and they were not 

 therefore critically examined until they were 18 hours old, when it was 

 discovered that 00 per cent of them were impregnated, but over half of 

 them seemed abnormal, the discs being spread out more than usual and 

 many being segmented in patches or clusters. They were again exam- 

 ined on the 21th, and it was found that 10 per cent of them plainly 

 showed well-defined twin discs, and three triplicate discs were discov- 

 ered out of some 500 eggs examined. They were kept under observa- 

 tion from day to day, and micrographs taken. It was also observed 

 that there were many eggs in this lot containing insufficient yolk-sacs. 

 This led to an examination of several other lots of eggs taken late, 

 which in turn revealed the fact that the late eggs contained a much 

 larger percentage of insufficient yolks than those taken earlier in the 

 season. It has been noticed each season since this station was estab- 

 lished that the late eggs did not turn out as well as those taken at the 



