Enemies of the American Oyster 153 



stomach, so to overcome the difficulty, nature has made 

 it possihle for the stomach to go to the food. The 

 greater part of this sack-like organ is made of a very dis- 

 tensible wall. This now begins to roll out of the mouth 

 and between the valves of the oyster's shell in the form 

 of a great thin sheet. It is spread over the soft tissues 

 of the victim's body, the great digestive glands connected 

 with the stomach cavity, pour out their secretion through 

 the tubular passage remaining in the center of the sheet, 

 and the food is rendered fluid and absorbed without be- 

 ing disturbed from its position within the shell. When 

 the meal is finished, the muscular part of the stomach is 

 slowly contracted and rolled back through the mouth 

 into the body. 



The starfish would not be so great a menace to the 

 oyster industry if its appetite were not so nearly insati- 

 able. It may live for months practically without food, 

 but having the opportunity, it will creep from one 

 bivalve to another — whether oyster, clam or mussel — 

 without observing a between-meal period, and thus be- 

 comes extremely destructive. A small star has been ob- 

 served to devour more than fifty clams somewhat smaller 

 than itself in six days, and increased in size at a very 

 rapid rate. 



It may be interesting to notice that this gluttonous 

 habit, certainly one of the most remarkable observed 

 among animals, begins in infancy, even at a time when 

 the arms are as yet mere rudimentary lobes on the sides 

 of the minute central disk. Figure 57 represents such a 

 precocious infant engaged in the destruction of a baby 

 clam. That this is beginning a life of ravin early, may 

 be indicated by the fact that the bodies of the two ani- 

 mals together measured less than two millimeters across. 



