412 E. p. CHURCHILL, JR. 



of emaciation between those that had been in the solution and 

 those that had not. The criteria taken into account in judging 

 the degree of emaciation were shrinkage of the cells and loss of 

 capacity of the cytoplasm of taking up the eosin stain. Many 

 workers on starved tissues have described great shrinkage and 

 loss of staining capacity on the part of fasting cells. Morgulis, 

 Howe and Hawk ('15) found that the cytoplasm of the cells 

 of a dog which had suffered extreme starvation took a much 

 less pronounced eosin stain than the cells of normal tissues. 



The cells of the mussel which had been in f Itered water for 

 ten days showed no appreciable signs of emaciation. Various 

 portions of its tissues were compared with corresponding parts 

 of those of the individual from the solution, special attention 

 being given to the epithelial cells of the gills in all the starva- 

 tion experiments. In making the tests with the eosin stain a 

 slide holding the sections from the mussel which had been in 

 the solution was placed back to back with a slide of the sections 

 of the control and both were passed through the alcohols and 

 eosin together. In this way it was certain that both were ex- 

 posed to the action of the reagents for exactly the same length 

 of time and that any difference found in depth of stain was due 

 to a difference in the cells and not to a variation in the time 

 the tissues had remained in the stain. In some cases sections 

 from mussels to be compared were mounted on the same slide. 



In the comparison of the mussels killed at the expiration of 

 thirty days, marked differences were found between the cells 

 of those that had been in the solution and of those which had 

 been in filtered water only. These differences were especially 

 noticeable in the cells of the gills. The cells of the mussels 

 which had been in the solution were plump, unshrunken and 

 took the eosin stain in a normal manner. The gill filaments 

 of those from the filtered water were small and wrinkled. The 

 cells were shrunken and took a much hghter eosin stain than 

 did those of the mussels from the solutions. Figures 11 and 12 

 represent respectively filaments of the mussel which had been 

 in filtered water and of the one which had remained in the solu- 

 tion of albumin. These figures show most clearly the shrinkage 



