KEPOKT OF C0MM1SS10^•EK8 OF i:NLA^J> FISIIEKIES. 25 



XII. What are the habits of the young star-fish'/ { It is possible 



that the young star-fish, like the young of many fish, tend to 

 gather in schools. If so, the young might be killed off in 

 thousands.) 



I have nieutioiied some of the habits of the youug stars under 

 the previous heading. There is little doubt that if the eel-grass 

 were cleared out they would be destroyed in great numbers. 



XIII. What is the rate of growth up to sexual maturity 9 



As far as I am aware this is not known. By arranging the star- 

 fish according to size Mr. Agassiz has estimated roughly that it 

 takes about fourteen years to reach full development, but that 

 they may become sexually matured in about six years. I have 

 been unfortunate in losing many of the specimens which I had 

 under observation. 



XIV. What is the size a7id age at sexual maturity ? 



I have made and tabulated some observations to determine the 

 size of the star when it first begins to breed, and believe that it 

 does not reach maturity until it measures two inches from the 

 mouth to tip of arm, and rarely until it is even larger. This con- 

 clusion must necessarily be provisional. 



XV. What are the natural enemies of the star-fish f 



Fresh water and extreme cold are most effective in killing off 

 star-fish. Heavy rain storms and freshets so freshen the water in 

 estuaries and shallow bays that great numbers of stars are killed, 

 though the oysters are not harmed. The freshet of March, 1888, 

 practically annihilated the stars on the extensive oyster beds in 

 Kickemuit river, as I am told b}^ the proprietor, and they were 

 not again a serious menace till three or four years later. I have 

 started some experiments to ascertain the least density of water 

 compatible with the life of the star. 



The free-swimming "fry" of the star-fish fall prey to many 



