88 THE LIFE OF THE SALMON 



salmon (S. solar) which is more or less spotted about 

 the operculum and shoulder, has maggots in its gills, 

 and which when cut up is found to be pale in the 

 flesh. It is not the bull-trout of the Tweed and 

 Coguet, otherwise called the round- tail. These 

 Tay bull-trout are not at all uncommon as fish 

 of over 40 lb., and the natural presumption seems 

 to be that they have their peculiar appearance 

 through having adopted a more estuarial habit and 

 different feeding than is common with normal S. 

 solar. From Tay salmon which have been described 

 as bull-trout on recapture eight examples may be 

 selected. Four of them show the short period, and 

 four the long period ; two were described as un- 

 spawned grilse on marking. The particulars are of 

 some interest, and are as follow : * 



SHORT PERIOD. 



A 6 lb. Kelt after 196 days increased 6 lb. 



4 )) )> l " 11 "i 11 



7f Unspawned Grilse 265 4 



j) 5-J 11 11 ^"^ 11 11 ^ 11 



LONG PERIOD. 



A 14 lb. Kelt after 556 days increased 19 lb. 



*" )> i) 447 ., ,, 4 ,, 



556 8J ,, 



1^ 525 ,, ,, lo 



Here the uniformity is seen to be in the short 

 period fish and a very marked extreme in the long 

 period fish, but we must recollect that possibly the 



* " Arretor," Proc. Eoy. Soc., Edin., XXV. Part I. p. 27. 



