NATURAL HISTORY OF BRITISH SALMONIDZ. 171 
same time. From the experiments of Dr. Davy, elsewhere 
commented upon, it appears probable that at least a propor- 
tion of trout, like some salmon, spawn only in alternate years. 
The situation chosen for, and the mode of conducting the 
spawning process are very similar to those noticed in the 
salmon—the eye, however, of the young fish becoming visible 
in about three weeks, and the egg being usually hatched in 
from forty to fifty days. , 
The yolk bag is absorbed in from three to five weeks ; and 
in six weeks or two months the young fly are about an inch 
long and able to shift for themselves. From this time their 
growth is rapid or slow according to the nature and quantity of 
their food and other local circumstances. 
THE GREAT LAKE TROUT. (Salmo ferox.) 
This fisn 1s the ‘ Ullswater trout’ and ‘grey trout’ of the 
English lake district, and the ‘Buddagh’ of Lough Neagh, 
where the smaller fish bear the local name of ‘dolachans.’ 
Though probably distributed throughout almost all the larger 
and deeper lakes of Scotland, it is, perhaps, best known amongst 
fishermen as the species for which Loch Awe is celebrated. 
It is found, to my own knowledge in Lochs Ericht, Lochy, 
Garry, and Laggan, and has also been recognised in Loch 
Shin, Loch Rannock, in Lochs Loyal and Assynt, and amongst 
some of the Orkney and Shetland Islands, , 
Besides Lough Neagh, the Great Lake trout is an inhabitant of 
all the largest Irish lakes—Loughs Mask, Melvin, Earn, Corrib, 
&c.—and is, in fact, almost wholly confined to similar great 
lakes and deep extensive tracts of water, where it reigns in 
more or less solitary grandeur, never leaving the lake except 
for the purpose of spawning—a process which commences 
about September or October—and then seldom venturing far 
up or down the tributary lake streams. In the river Awe, for 
example, the outlet from the lake best known in connection with 
