MIGRATION OF SALMON-FRY 267 



26. Q. What is the age of the fry when they 

 leave the river for the sea ? 



A. About eighteen months old. 



27. Q. Is there any particular month in which 

 the salmon-fry leave the river for the sea ? 



A. In April and May, but principally during 

 May. 



28. Q. What is the principal cause which fixes 

 the time of the migration of salmon-fry ? Is it 

 the temperature of the water, or their assumption 

 of a silvery dress, or both ? 



A. The assumption of the scales, and being 

 thereby fitted to take to the salt water, and 

 impelled by natural instinct to go to the sea. The 

 higher temperature of the water acts as a further 

 inducement to them to take their departure. 



29. Q. Assuming that the young fry become 

 parr, and that the parr become smolts, and that 

 the smolts, when they acquire the silvery scales, 

 leave the river, state the age of the fish when they 

 become parr and smolts respectively. 



A. They become parr from the date of their 

 hatching out, and smolts when a year old. 



30. Q. Have either parr or smolts been 

 observed with ova or milt in them ? 



A. The male parr have milt fully matured in 

 them. The females are never known to have 

 developed ova. 



31. Q. Have parr ever been seen to go to the 

 sea? 



