THE CALIFORNIAN SALMON. 91 
albumen, is completed ; tbe young fish becomes too 
large for its prison, and the shell bursts open, liberating 
the captive. AVhere there are many ova hatching out, the 
observer maybe fortunate enough, to see this very interest- 
ing phenomenon take place before his eyes. Sometimes 
the head comes out first, and the shell adheres to the sac 
for a time, till a last grand effort frees the young alevin 
which lies panting with the exertion, and the novelty of its 
position, exercising vigorously its lungs, or the breathing 
apparatus in its gills, which performs the same oflB.ce. 
At first a few fish will hatch out during two or three 
days, and then the great bulk of them will come, the whole 
being hatched in about ten or twelve days, and some 
unimpregnated ova in which no fish exist will remain good 
and sound to the last. 
During the time of hatching, the watering-pot should 
be used freely, and indeed all through the time of incuba- 
tion, when sediment becomes troublesome. When the 
hatching is going on, the empty shells and deivis of the 
eggs, are by it washed away and get collected against the 
screens, when they can be removed. The current of water 
should now be increased a little, and a slightly higher 
temperature is not objectionable. The alevin stage of the 
fish, is the least troublesome time in the rearing of young 
trout or salmon. They do not require any food, and are 
little liable to loss at this period. A little very fine earthy 
gravel, should be spread over the coarser gravel in the 
hatching boxes, to cover up and deodorise any particles of 
decaying eggs which may be in the gravel. Of course all 
dead fish should be removed at once, as decay sets in very 
speedily. Every second day, a sprinkling of fine volcanic 
earth, or good loam not of an adhesive nature, is very bene- 
ficial, and it should be scattered over the surface of the 
water. The shower should be used two or three times 
