262 American Fisheries Society 



The thickness of the ccecal wall and the diameter of the 

 cavity within vary according to the degree of distension 

 of the tube. 



The detail of the histological structure is comparable to 

 that of the intestinal tube of which the cceca form diverti- 

 cula. The ccecum is covered with peritoneum and lined on 

 the inside with a simple layer of mucous epithelium much 

 folded. Listing all these coats and naming the parts from 

 without inward they are : The serous coat, the longitudinal 

 and circular muscular coats, and the mucous coat, consisting 

 of the tunica propria, the stratum compactum and the 

 mucous epithelium. 



Method of observation. — The method used for the ex- 

 amination of the amount and histological distribution of 

 fats was the newer modification of the Herxheimer method 

 for staining fat with scarlet red, a method which has been 

 recently improved and used with much success by Prof. 

 E. T. Bell, now of the University of Minnesota, and his 

 assistants. By this method portions of fresh tissue, or 

 material that has been for a short time in ten per cent for- 

 malin, are sectioned by the freezing microtome method, 

 transferred into seventy per cent alcohol, stained with alka- 

 line alcoholic solution of scarlet red, and mounted in pure 

 glycerine. Preparations sealed with paraffin keep more or 

 less perfectly for a few weeks only. 



Observations and hypotheses. — During the examination 

 of the different tissues of the king salmon taken off the 

 feeding grounds at Monterey Bay. Cal., it was noticed 

 that varying quantities of fat droplets were always found 

 in the pyloric cceca. The fat was located always in the 

 epithelium and in that portion of the mucous coat described 

 as the tunica propria. In certain preparations immense 

 quantities of fat droplets were crowded into the cells of the 

 epithelial coat. This loading of the epithelial cells with fat 

 formed indeed a very striking picture. However, in sec- 

 tions prepared from different animals, and, in fact, often in 

 different regions of one and the same section, the loading of 



