l6 HOME FISHING AND HOME WATERS. 



encumbered with a yolk sac, larger in bulk than all 

 the rest of it put together; this sac extends from 

 the gills to the vent, and as long as this remains, 

 the little fish does not require food. The length of 

 time the sac remains on the fry, varies with different 

 kinds offish. With the fall-spawning kinds of fresh 

 water fish, as the brook trout, salmon trout, salmon, 

 etc., it usually requires from thirty to forty-five days, 

 before it is absorbed. With the fish which cast their 

 spawn in the spring and summer, as the bass, shad, 

 perch, etc., but a few days are required before they 

 are relieved of nature's nursing bottle. One great 

 reason why a larger percentage of the spawn and 

 young fish of the spring spawners survive, is because 

 it takes them such a short time to hatch and develop 

 sufficiently to protect themselves from their enemies, 

 by escaping and hiding. While the fall spawners, 

 which are from sixty to one hundred days, and some- 

 times even longer in hatching, are much more liable 

 to be destroyed. The difference in the time of 

 hatching, depends upon the temperature of the 

 water; the warmer it is, the sooner they hatch. 

 With the spawn taken in the fall, each degree of 

 warmth in the water hastens the hatching period five 

 days, and each degree of cold retards it for the same 

 length of time. While with the spring spawners, 

 each degree of heat or cold, makes about one day's 

 difference in hatching. 



