4 THE SPORTING FISH 



bars on their sides until shortly before their migra- 

 tion, up to which period they are Parrs ; they then 

 invariably assume a more or less complete coating 

 of silvery scales and become S molts, the bars, or 

 Parr-marks, however, being still clearly discernible 

 on rubbing off the new scales. 



6. The young of all the species here included in 

 the genus Salmo have at some period of their ex- 

 istence these bluish bars ; and consequently such 

 marks are not by themselves proofs that fry bearing 

 them are the young of the true Salmon (Salmo 

 salar). 



7. Unless the young fish put on their Smolt 

 dress in May or early in June, and thereupon go 

 down to the sea, they remain as Parrs another 

 year ; and without Smolt scales they will not 

 migrate, and cannot exist in salt water. 



8. The length of the Parr at six weeks old is 

 about an inch and a half or two inches ; and the 

 weight of the Smolt before reaching the tidal wave 

 from one to two ounces. 



9. In at least many cases, Smolts thus migrating 

 to the sea in May and June return as Grilse, some- 

 times within five, generally within ten weeks, the 

 increase in weight during that period varying from 

 2 to 10 Ibs., the average being from 4 to 6 Ibs. ; 



