MANUAL OF FISH-CULTURE. 243 



fry are aiiowed to each can — tlie number depending on the length of 

 the trip and age of the fry. These fish are moved as soon as the sacs 

 are absorbed, or when tliey first begin to swim up from the bottom. If 

 shipped before this period of life, they are liable to collect on the center 

 of the can in the bottom and smother. If the fry will keep away from 

 the mouth of the can, the water is aerated by dipping it directly from 

 the can and letting it fall back; but if the fish do not go down when 

 the dipper is introduced, the water is siphoned into a pail, aerated, and 

 then poured back. 



Small yearling trout are sometimes carried in cans, but usually in 

 the galvanized-iron tanks; 100 to 200 are put in each can if the air 

 circulation is used, and the water is kej)t cool by introducing ice. As 

 salmon and lake trout are more delicate than the others, the number 

 placed in each can is reduced. When shipping adult trout but few can 

 be taken in each tank, only from 20 to 50 if they are of large size. 

 They are given all the air and water circulation possible and carried at 

 a low temperature. Incessant watchfulness is necessary in moving 

 these fish. When the fish are in distress they come to the surface of 

 the water, and if the water is then vigorously aerated they will return 

 to the bottom of the tank. 



When black bass are distributed in the fry stage they should be 

 shipped in water from 40° to 60° F., according to the temperature tof 

 tbe water from which they are taken; but it is considered preferable 

 to bold these fish in the jDonds or feeding-troughs until they are from 

 three to six months old, when they will have attained a length of from 

 1^ to 3 or 4 inches, fish hatched at the same time often varying consid- 

 erably in lengtli. These older fish also require a temperature of from 

 40^ to 60°, according to circumstances, when they are transported. 

 Yo\ing black bass are very voracious, and begin to eat each other as 

 soon as they are confined in cans or tanks for transportation. The 

 number of bass carried in each tank is approximately as follows : Fifty 

 8 to 12 inches long; one hundred and twenty 5 to 8 inches long; two 

 hundred and fifty 2 to 5 inches long. 



Crappie are carried in the same manner as black bass, although it 

 is more difticult to handle them. Rock bass are commonly carried in 

 cans, about 500 to 700 in each if the fish are about an inch long. The 

 temperature of the water is from 40'^ to 60°. 



Codfish fry are moved in cans with water of a temperature of 33° to 

 38°. The trips are usually of short duration. The water is aerated 

 by drawing it from the can through a screen siphon into a pail and 

 returning it after it has been thoroughly aerated. 



Large lobsters, on long tri])s, are packed in seaweed in wooden trays 

 about G inches high and of a size convenient for handling. Strips of 

 wood attached to the bottom of trays have open spaces between them 

 to allow air circulation. About 2 inches of seaweed are spread on the 

 bottom of the tray and the lobsters placed on it with their claws 



