REFORMATION OF THE CRYSTALLINE STYLE 287 



That the extraction of the crystalline style does not affect the 

 tenacity of life of the animal when out of water is shown by the 

 fact that I have been unable to keep normal individuals alive 

 under low temperature for a longer period than fourteen days. 

 That Mya arenaria may, however, exist for a longer period than 

 fourteen days, without taking food, when under normal condi- 

 tions, has previously been shown by experiments 3, 4, and 5. 



7. THE SOURCE OF THE CRYSTALLINE STYLE 



The source of the crystalline style and the manner of its forma- 

 tion have been subjects of conjecture and considerable contro- 

 versy even among those to whom the digestive function was ac- 

 ceptable. To consider the stomach the source of the crystalline 

 style was the logical result of the 'reserve food' theory. This, 

 however, failed to explain the concentric layers as observed in 

 sections of the organ. That the crystalline style is formed by 

 secretions of the liver gland, that it is a product of the cells of 

 the wall "of the stomach, that it is secreted by the epithelium of 

 the style sac itself, have each had its supporters. 



Mitra ('01), concluding as did Coupin ('00) that the crystalline 

 style contained digestive ferments, believed, however, after find- 

 ing granules in the substance of the style similar to those of the 

 liver, that this gland must be the source of the organ. 



List ('02), Gutheil ('11), and Nelson ('18), after extensive work, 

 concluded that the crystalline style was a product of the style 

 sac, the typhlosoles furnishing the material of secretion entering 

 into its formation. 



In connection with the source of the crystalline style, the func- 

 tion of the different types of cells lining the style sac has been 

 the subject of many speculations and theories. Respecting the 

 cells of the general surface of the style sac in Mytilus edulis, 

 Sabatier ('77) says: "The particular aspect of these cells, their 

 richness in granular protoplasm, leads me to consider them es- 

 pecially as an epithelium of secretion destined to furnish a diges- 

 tive fluid to the stomach."" He adds, "The length and force of 



2 My translation. 



