Shir a. — Rearing the Channel Catfish 83 



flat surface in the jar upon which they could rest they 

 congregated in a dense mass at the lowest point in the jar 

 under the unhatched eggs. In an effort to remedy this, 

 the eggs were removed to a round, rather flat-bottomed 

 glass aquarium of about 6 litres capacity, supplied with 

 a tube from the hatching battery. This gave the fry an 

 opportunity to scatter out over the bottom of the glass 

 vessel and no further loss resulted. By 5 : 00 P. M. on this 

 same date all had hatched, 706 strong and healthy fry 

 having been obtained. In addition, 164 fry had died and 

 150 eggs had been lost during the hatching period, mak- 

 ing in all 1,020 eggs that had been removed from the nest 

 in the pond. 



The eggs averaged 3.53 mm. (about 0.14 of an inch) 

 in diameter and the young when hatched were about one 

 half an inch long, were quite slender, and very transpar- 

 ent. The yolk sack was quite large and oblong, making 

 up about V t the length of the fish, and of a rather light 

 amber color. By July 13th, the yolk sac was almost 

 wholly absorbed. The fry kept very close to the bottom 

 of the container and made little effort to rise. 



Of the fry that had hatched in the pond, 2,861 were 

 obtained. Of this number 802, including those found 

 dead in the keg, were lost in the process of handling, due 

 to the fact that they were entangled in dense masses 

 of algae from which they were removed with difficulty. 

 The temperature of the water at the time of removal was 

 95° F. Of the 2,059 living ones, 1,717 were returned to 

 Pond 9 D, July 8, after removal of adults ; 300 placed in 

 Pond 1 E, July 8, a new pond with an area of 0.046 acre; 

 30 placed in an aquarium, and the remainder preserved 

 for specimens. The 706 fry hatched in the jar were dis- 

 posed of as follows: — 300 placed in Pond 4 E, July 11, a 

 new pond with an area of about 0.046 acre; 374 placed 

 in Pond 9 D with the older fry, July 11 ; and the re- 

 mainder preserved as specimens. 



Growth 

 Beginning July 25, collections, almost weekly, have 

 been made in the ponds, and the young fishes secured 



