24 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



presses out the eggs. Oue mau dips the male fish from their com- 

 partment and places them on the floor of the platform directly behind 

 the two men who handle them. Oue holds the fish by the head and the 

 other presses out the milt with one hand as he holds it by the tail with 

 the other, the milt falling into the same pan that receives the eggs and 

 practically at the same time. 



The eggs and milt are gently stirred with a feather in the spawning- 

 pan as they are expressed from the fish, and the pan is then placed 

 upon a shelf under a dark curtain, where it remains for li minutes, 

 when the contents are poured into a large galvanized iron bucket nearly 

 full of water, the eggs being placed therein before adhesion takes place. 

 During the season of 1896 a total of 4,968 females were stripped, 

 producing 25,852,880 eggs. The greatest number of females stri^^ped 

 in any oue day was 269, yielding 1,392,000 eggs. The spawning crew 

 became very i)roficient, having stri})ped as many as 151 females in 60 

 minutes. Spawning usually takes place during the afternoon and 

 seldom exceeds 2.J hours of active work. 



The eggs are transferred by wagons from the si)awuing platform to 

 the hatcheries in large galvanized-iron buckets, 15 inches deep and 14 

 inches in diameter, which, when filled with water, hold about 70,000 

 eggs. The tops of the buckets are covered with canvas, and the 

 average length of time occupied in taking the eggs, transferring them 

 to the hatcheries, and measuring them into the hatching-baskets is 40 

 minutes. 



The two hatcheries at Battle Creek contain 160 hatching-troughs, 08 

 of those iu the building first erected being 16 feet by 16 inches by 6^ 

 inches, while half of the 92 in the other building are of the same size, 

 the remainder being 16 feet by 12 inches by 6^ inches. A head or 

 distributing trough runs lengthwise of each building and receives the 

 water from the settling-tank on the outside. The hatchiug-troughs are 

 arranged in sections of four bound together. Two abut against the 

 distributing-trough, from which they take their supply of water and 

 carry it to the two troughs below, whence it passes to the escape 

 drain at their lower ends; 24 gallons of water per minute are admitted 

 to each trough, and the average temperature of the water is 52°. At 

 the head of each hatching-trough, 2 inches above the surface of the 

 water, is i»laced a tin aerator, 10 inches by 4 inches by li inches, the 

 bottom only being perforated; 4 inches from the lower end of each 

 trough a retaining-screen is jilaced at an angle. Between the screen 

 and the end there is a 2-iuch hole in the bottom stopped with a plug 

 which i)rojects above the surface of the water. In cleaning the trough 

 this plug is removed, the increased flow of water causing a strong 

 current through the entire length of the trough, which has a capacity 

 of 200,000 eggs coutaiued in five trays or baskets. 



When the eggs reach the hatchery they are washed, measured, and 

 placed in the hatching baskets or trays, 40,000 beiug placed in the 

 16-mch and 25,000 in the 12-mch trays. These are made of galvanized 



