SPA WNING. 23 



CHAPTER IV. 



SPAWNING. 



\\ 7HEN cold weather fairly sets in, sooner or 

 * * later, according to river and season, the trout 

 run up into the small side streams, where shallow, 

 rippling water and bright gravel are to be found, 

 though many of the larger and older fishes spawn in 

 suitable parts of the main current of the river more 

 especially in the case of the larger varieties of S. Fario, 

 S. Thymullus, or Grayling, and the lordly Salmo Salar 

 sometimes they arrive in herds, sometimes in pairs 

 sometimes individually. The duration of the 

 spawning time varies according to the various circum- 

 stances of the season, river climate, and many other 

 causes. Sometimes the business will be concluded in 

 a few days, so that diligent watch has to be kept, in 

 order to secure the required amount of ova for 

 artificial impregnation, at others it may extend over 

 eight or ten weeks, batches of fishes following each 

 other in succession, more especially in those places 

 where fresh strains have been imported to cross with 

 the original or indigenous one, in order to improve 

 it either in size, beauty, gameness, or some other 

 characteristic. 



Before the spawning season is expected to com- 

 mence, the stream should, as far as possible, be cleared 

 of mud or any thing likely to prove injurious to the 



