326 PROCEEDINGS OF THE ACADEMY OF [May, 



escape of the fluid secretion all along the line, and must do so at 

 the extreme posterior end (figs. 3, 4), is such as the distribution of 

 the secretion would require — all these considerations seem to the 

 writer to constitute a strong chain of evidence that Lereboullet' s 

 view^ is the correct one, namely, that it is the primary purpose of this 

 structure to distribute the secretion. That it did not develop on the 

 ventral side in direct connection with the opening of the glands, in- 

 stead of on the dorsal side, is remarkable. Certainly, this would 

 seem to be the more natural position for a structure concerned in 

 the distribution of a secretion which enters on the ventral side; 

 because it would be the more certain of finding its way into the 

 channels if they occurred on this side. ' ' Nevertheless, ' ' as Lere- 

 boullet says, " one can understand that in the movements of con- 

 traction of the stomach a part of the secretion (bile) may flow by 

 these canals." 



VII. Absorption of Carbohydrates. 



Tliis class of food substances is not at all favorable for a study of 

 absorption by morphological methods. It is evident that none of 

 the reagents ordinarily employed as fixatives act on carbohydrates 

 in solution so as to render them visible to the microscope. A 

 word on the digestion of starches, however, may not be without 

 interest in this connection. Huet has found that the salivary glands 

 (which Ide calls cutaneous glands) of Ligia produce diastase, and 

 it is evidently to the secretion of this organ rather than to that 

 of the hepatopancreas that he would ascribe the diastatic action 

 in the intestine.^® No effort has been made to confirm either 

 Huet's or Ide's conception of the nature of the glands in question. 

 It seems unlikely that a gland so small could have much to do 

 with the action which we have now to describe. 



Starved animals were fed on various kinds of starch, — cold-boiled 

 potato, corn starch, dry bread, etc. The former proved to be espe- 

 cially palatable for some very large specimens of Onisetis which 

 happened to be on hand at the time. They were allowed to eat 

 freely of it for half an hour, in which time the intestine was com- 

 pletely filled. Twenty-four hours after they were killed, and the 

 whole intestine subjected to Moore's test for sugar. Splendid 



*' Since he found the diasUxtic action of the "liver" secretion of Ligia 

 only slight. 



