14 SALMONID.E. 



water being destroyed by contact with tlie fresh, and vice 

 versa. 



The fry are observed to collect in small pools and mill-dam 

 heads preparatory to quitting the river. The specimen from 

 which the figure on the page was taken was obtained in the 

 Thames, in which river they are occasionally caught in the 

 season, with other fry of Salmonid<z, by fishermen who work 

 at night with a casting-net on the gravelly shallows for Gud- 

 geons to supply the London fishmongers. 



My own specimens of the young of the Salmon having 

 been preserved in spirits, and the colours thereby affected, 

 the following description is from Dr. Heysham's Catalogue 

 before referred to, premising that some differences in colour 

 may be expected in specimens from different rivers. 



"Length seven inches and a half; circumference three 

 inches and one-eighth : head dark green ; gill-covers fine 

 silvery white, marked with a dark-coloured spot ; belly and 

 sides up to the lateral line of the same silvery colour ; 

 back and sides down to the lateral line dusky, inclin- 

 ing to green ; sides above the lateral line marked with 

 numerous blackish spots ; along the lateral line, and both a 

 little above and beneath it, several dull obscure red spots : 

 dorsal fin has twelve rays, marked with several blackish 

 spots ; pectoral fin has twelve rays, of a dusky olive colour ; 

 ventral fin eight rays of a silvery white ; anal fin ten rays of 



