148 DB. W. C. M'INTOSII on the rOOD AND 



gravity is in accordance witli the medium. At any rate, and 

 whatever be the explanation, the presence of these crystals is an 

 interesting physiological fact. In a greater number of instances 

 than in the case of the stomach, bones, lenses, and other dense 

 textvires occurred in the intestines ; for they were present in several 

 instances where no trace occurred in the former, and vertebrae 

 could readily be detected as far down as the anus. In addition 

 to those in which the debris of ascertained food in the stomach 

 was found in the intestines, I met with crustacean hairs in several 

 instances, Diatomacese, sand-particles, fragments of an insect, 

 masses of solid fat, and portions of liver belonging to a fish like 

 the Sparling. In every other instance there was nothing in the 

 intestinal tract but parasites, mucus, crystals, and an abundant 

 supply of fatty globules and particles of all sizes. The rapidity 

 and power of digestion in this fish is extraordinary ; but there is 

 no doubt that, if the fish had fed regiJarly, the food could never 

 have disappeared so rapidly and well as to defy even a microscopic 

 investigation of the intestinal tract throughout. It is, however, 

 a mistake to suppose that they never feed in fresh water at all, 

 just as it is one to suppose that they feed voraciously, but vomit 

 their food when captured. The true state of matters would seem 

 to be that the salmon when in fresh water feeds rarely and at 

 intervals, but not from want of voracity, as the contents of the 

 stomachs above mentioned show ; and further, that such food is 

 occasionally found in its stomach from February till August *. 



Ectozoa. — I had only the opportunity of examining about a 

 dozen grilse and salmon for these parasitic animals, and the sole 

 species foun^ within the period above mentioned was Lepeoph- 

 theirus Stromii (Baird) — four males and three females. They 

 occurred at the base of the fatty fin, at the base of the caudal rays, 

 in the socket of the eye, and in front of the hyoid apparatus — 

 and all in grilse. 



Nothing whatever occurred on the branchiae to attract attention 

 but once ; and this abnormal appearance proved to be non-parasitic. 

 A number of large villi proceeded from a bulging and thickening of 

 the arch, but solely attached to the cutaneous textures. The villi or 

 processes were fibro-cellular in structure, and contained at their 

 bases numerous black pigment-corpuscles and crystalline masses. 

 They seemed to be morbid growths of the fibrous textures of the 

 region. 



* They have also been seen to void several vertebrae per anum, when landed 

 on the bank of the river. 



