HOW DO STARFISHES OPEN OYSTERS? 285 



In order to afford an idea of the rapidity with which a starfish 

 completely devours an oyster or bivalve, I may mention that a starfish 

 of moderate size had completely digested a Venus 3 7 cm. long in 

 81- hours, and an oyster 2 J, cm. in diameter, which was given it open, 

 in 4 hours. 



In conclusion, I would point out that the oyster or mussel culturist 

 should take the greatest pains to destroy starfishes wherever and 

 whenever he can get hold of them. It is not sufficient, however, 

 to tear them up, since they possess an extraordinary power of regenera- 

 tion, and are able to replace lost parts in a relatively short time. The 

 central body especially plays an important part in this process, and it is 

 probably for this reason that (according to Forbes) regulations exist 

 in certain parts of England which oblige the fishermen to tear or crush 

 the central body of starfishes which they capture, before throwing 

 them overboard. In many districts it would no doubt be worth while 

 to bring the starfishes ashore, and use them as manure. The practical 

 Americans have constructed a special dredge — the " star dredge " — an 

 iron instrument carrying a number of tangles, with which they syste- 

 matically capture starfishes on the oyster beds. 



