268 American Fisheries Society 



amount of fat in this region was considerably increased 

 over that in the normal animal. Different portions of the 

 tunica propria are not uniformly charged with fat droplets. 

 The fat extends down to the stratum compactum, but not 

 beyond in any case. It seems that the stratum compactum 

 acts as a definite bounding membrane to the mass move- 

 ment of the fat in the submucous layer. Apparently the fat 

 is taken from this region by some mechanism acting through 

 the agency of the circulatory system. 



Various sections of the pyloric cceca revealed the same 

 general picture of the passage of fat droplets through the 

 mucous epithelial coat that has previously been described for 

 fish no. 45. The fat was present in surprisingly large 

 drops in the outer layer or zone of the epithelial cells. It 

 was also present in the basal portions of these cells and 

 present in considerable quantities in the underlying tunica 

 propria. 



The intestinal tract in all the regions of no. 46 examined 

 showed fat in process of absorption through the mucous 

 epithelium. 



One individual of the smaller sized salmon was examined 

 with reference to the fat absorption. It showed a picture 

 structurally comparable to that of the larger salmon. The 

 very small diameter of the pyloric cceca renders their ex- 

 amination relatively difficult,, yet the details of the distribu- 

 tion of fat in the mucous epithelium can only be interpreted 

 as confirming the deduction made from the two larger 

 specimens, i. e., that the fat fed in these experiments tats 

 being actively absorbed by the pyloric cceca and the intestine. 



DISCUSSION 



Dr. H. B. Ward, Urbana, 111.: I would like to ask a question. Do 

 I understand that you used salmon that had passed out of salt water 

 mto fresh water, or were they king salmon still in salt water and 

 feeding? 



Dr. Greene: The first experiments were on naturally feeding salt- 

 water king salmon : the experiments in which I myself fed the fish 

 artificially were on young king salmon that had not yet gone into salt 

 water — some of them were two and some one year old. 



