THE SALMOX FAMILY. 359 



rapid torrents, being mucli more prone to going down 

 than up stream. It has the power, however, of raising 

 itself rapidly to the surface, and of descending again with 

 stone-like velocity — a faculty which has been ascribed to 

 the action of the large dorsal fin striking either upwards 

 or downwards against the current, but which is more pro- 

 bably attributable to the unusual size of the swimming- or 

 air-bladder. 



The ova of the Grayling are numerous, but considerably 

 smaller than those of the Trout, being about the size of 

 partridge- shot, and when viewed in the rays of the sun 

 have very much the colour of the opal. The body of the 

 embryo fish becomes distinctly -i-isible in about nine days, 

 and the egg itself hatches in fourteen or fifteen days from 

 the date of deposit, — results obtained in the case of the 

 eggs of the Trout in about thirty-five and fifty days re- 

 spectively. 



Their spawning-time is in April or the beginning of 

 May, the fish getting into condition in July, and reach- 

 ing its prime in October and November, when most of the 

 other Sahnonida are going ofi'. The Grayling has, more- 

 over, the advantage of rarely being so much out of season 

 as to be unfit for food, or unwilling to take a bait if judi- 

 ciously ofiered. Sir Humphry Davy, who has given us a 

 very fair history of the fish, considered that it might be 

 fished for at all times of the year, and that when there 

 were flies in the water it would generally take them. 



In the winter months the Grayling will commonly rise 



