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POPULAR SCIENCE MONTHLY. 



Sacramento pike and split-tail. Some of them, at least, are caught in 

 the eddies formed among the cobble stones, and are held near the 

 'nest,' or hillock of gravel thrown up by the spawning fishes. These 



Sacramento Salmon. 



are covered by the sand and protected, though many are covered too 

 deeply and are killed. 



Salmon ova are about .25 inch in diameter. The 'shell' is mem- 

 branous and finely porous, with a minute aperture, somewhat larger 

 than the pores, known as the micropyle. When first extruded the ova 



McCloud River, near Baird, a Typical Spawning Stream. 



are soft and compressible, and it is while in this condition that they 

 must be fertilized. Within two or three minutes after being deposited 

 in the water they become turgid, and are then incapable of fertiliza- 

 tion. 



