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pry into every cranny and crevice for them. Their 

 hunger is unsatiable and their energy untiring. But, 

 injurious as they are other dangers are more destructive. 

 A little increase of current will wash nine-tenths of the 

 eggs off the rocky ledge into the muddy flats where they 

 perish for want of aeration. A heavy rain will roil the 

 water, and on its subsidence there will be deposited up- 

 ori the eggs a thin covering of sediment which will 

 destroy them all absolutely and without exception. Eggs 

 of fish in order to hatch must be continually surrounded 

 with fresh water ; they require the oxygen of changing 

 water just as land animals require the oxygen of chang- 

 ing atmosphere. Shut a man in a small room, or a 

 mouse under a glass jar, and as soon as he shall have ex- 

 hausted the vitality of the air in the confined space he 

 will die. Fish and their eggs can be smothered in pre- 

 cisely the same way. A muddy deposit upon eggs 

 excludes aeration and death ensues to a certainty. There 

 is no exception to this rule, and this is the most fatal 

 peril to which shad spawn is exposed and which annually 

 decimates the yield of young fish. 



So great are these risks that shad could never have 

 held their own were it not for the compensation of their 

 wonderful fecundity. They produce ten thousand eggs 

 to each pound of weight, which is ten times as many as 

 salmon or trout and it is not unusual to obtain sixty 

 thousand eggs from a single mature female. This is 

 their protection, that among the vast number laid some 

 will hatch, and although the per centage is small the 

 aggregate has been large enough to maintain tho supply. 

 But here arises the most serious trouble when man inter- 

 feres with the established order of nature. Accident 

 sweeps away just such a proportion, the water and land 

 creatures which feed on the eggs will abate no jot or 



