266 American Fisheries Society 



not determine whether any of the oil was retained. The 

 specimens were therefore immediately fed pure olive oil. 

 this time by way of the rectum. 



A small quantity of oil was taken into a medicine drop- 

 per, the glass point of which had previously been drawn 

 out to the proper size. The tip of the dropper was then in- 

 serted through the anus into the rectum and the oil gently 

 injected until it was judged a sufficient quantity had been 

 used to fill the small intestine as far forward as the pyloric 

 division. Of the larger salmon one received a relatively 

 large quantity of oil, the other a smaller quantity. Of the 

 small salmon no attempt was made to differentiate them as 

 regards the quantity of oil used. 



All the fish were in good condition, were sprightly fol- 

 lowing the giving of the oil, and they remained so until 

 they were killed in the experiment. The first specimen, no. 

 45, 14 centimeters long, was killed after 19 hours. The 

 second specimen, no. 46, was killed after 42 hours. The 

 smaller fish were used as corroborative material and were 

 killed at later periods. 



Detailed results of the Brookdale salmon fat-feeding 

 experiment. — The young salmon, no. 45, was killed by 

 cutting off its head. The alimentary tract was carefully 

 removed and portions of it examined perfectly fresh, other 

 portions were fixed in formalin, and still other portions in 

 solutions preparatory to paraffin sectioning. The fresh 

 material was frozen and cut on the Bardeen freezing micro- 

 tome. The sections were cut into seventy per cent alcohol 

 and were immediately after stained in alkaline scarlet red. 

 Formalin fixed sections were also stained for fat. Later 

 paraffin sections were made for the study of structural 

 details. 



The cross sections of the pyloric cceca of the young 14 

 centimeter salmon show a comparatively simple folding of 

 the mucous epithelium, also the stratum compactum seems 

 relatively undeveloped and the cceca are correspondingly 



