442 



results, under the title "The Physiology of the Salmon in Fresh 

 Water", has recently appeared in the Journal of Physiology, Vol. 22, 

 No. 4, p. 333. 



A series of 118 salmons, provided by the Fishery Board, and con- 

 sisting of fish taken from the sea, from the estuary, from the upper 

 waters of the rivers, and of kelts, was subjected to investigation in 

 many difi'erent ways, and a large number of these fish were examined 

 histologically. 



The primary object of this part of the work was to ascertain 

 whether the salmon, in fresh water, is capable of digesting and 

 assimilating food, and the answer to this question must be in the 

 negative. 



The digestive tract of the salmon has not hitherto been the sub- 

 ject of any very detailed examination. Its general arrangement, of 

 course, conforms to that usual in the group of Teleosteans to which 

 it belongs, and it may here be divided into stomach, pyloric appen- 

 dages, intestine, pancreas, and liver. All of these were examined in 

 the series of fish under consideration. 



Method. 

 The same method of preparation was used in all cases in order 

 that the results might not be affected by any deviation in this respect. 

 As early as possible small portions of the organs above mentioned 

 were removed from the fish and were placed immediately in a satur- 

 ated watery solution of corrosive sublimate. After 24 hours they 

 were rapidly washed in water and then passed through a series of 

 alcohols increasing in strength. They were embedded in paraffin, cut 

 with the rocking microtome, and fixed to the slide by my water me- 

 thod. One set of sections was always stained with hscmatoxylin and 

 eosin, whilst other stains, especially the usual anilin dyes, were em- 

 ployed for comparison. The sections were all mounted in balsam. 



Literature. 



The digestive tract of the salmon has never been examined micro- 

 scopically with special care in recent times, but the stomach of the 

 nearly allied trout has been described by Valatour (1), Cajetan (2), 

 and OppEL (3). 



The most important contribution to the subject hitherto has been 

 that by Miescher-Ruesch (4), who found that the stomach and gullet 

 of the fish taken at Basel, far up the Rhine, were contracted and 

 folded, contrasting strongly with the distended stomach and gullet 

 of the salmon taken in the Baltic and North Sea. He noted the 



