284 CHARLES HOWARD EDMONDSON 



the secretion of the digestive juices without the voluntary regu- 

 lation of the food supply." The same investigator determined 

 that the molluscs continued to feed regardless of appetite, and 

 with regard to the crystalline style this observation was made: 

 "The crystalline style was found to disappear only with the lack 

 of food, and to be regenerated only when food was supplied, re- 

 gardless of time." 



My experiments with Mya arenaria seem to show that the 

 ingestion and digestion of food is dependent upon the degree of 

 development of the crystalline style, since not until this organ 

 is sufficiently mature to be projected into the stomach, where 

 the ferments which it contains may be of service, does the animal 

 ingest food. The appetite is wanting until the crystalline style 

 is functional. 



Expemnent 7. April 21, 1918 



Twenty-four glams with crystalline styles removed as in previous 

 experiments were planted under normal conditions. The test extended 

 for a period of sixty-nine days. 



Result, July 5, 1918. Ten of the clams operated upon April 27 were 

 alive and in good condition. The severed style sacs were healed, and 

 in nearly all of the specimens the cut ends were closed. In each surviv- 

 ing individual the proximal division of the style sac contained a crystal- 

 line style nearing a state of complete development (fig. 27). The crys- 

 talline style in each case occupied the entire length of the tube and pro- 

 jected into the stomach, but was not in actual contact with the gastric 

 shield. For a short distance from the distal end the style was closely 

 coiled to the right, the remaining portion of the surface being smooth. 

 The distal extremity was slightly larger in diameter at this period of 

 development. Some of the crystalline styles enclosed twisted cores of 

 food material. 



In the majority of the specimens of this experiment the short, distal 

 division of the style sac was entirely closed, forming a completely iso- 

 lated tube blind at both ends. These blind tubes were usually filled 

 with mud which collected in them before the severed ends healed, but 

 in one individual, on opening this blind portion of the style sac cut off 

 from the rest by the operation, it was found to be occupied not by for- 

 eign material, as in case of the others, but by a soft, gelatinous rod, ex- 

 tending the full length of the tube, which in all respects resembled the 

 substance of the regenerated crystalline style of the other division of 

 the tube. 



Here was a crystalline style developing in a portion of the style sac 

 entirely removed from any relation to the digestive tract, which would 



