268 THE ANGLEK-NATUKALIST. 



or maggot, which adheres firmly to the inside of the gill- 

 covers, and from which they are released by contact with 

 the salt water, a similar release from other parasites being 

 obtained on passing to the fresh water from the sea. 



Within a period of five or six months after their return 

 to the salt water, it has been proved that at least a propor- 

 tion of Kelts find their way back to the upper reaches of 

 the river as clean fish, having gained in weight during that 

 time from 7 to 10 Ibs. The Duke of Atholl has for some 

 years caused all Kelts taken with the rod in his waters to 

 be marked with a numbered copper or gutta-percha ticket 

 fastened to the tail, stating the time when caught and the 

 then weight, the increase of weight attained being also 

 noted upon the fish being subsequently recaptured. The 

 annexed table exhibits the increase of weight in three 

 instances. 



CAUGHT AS KELTS OR SPAWNED 

 FlSH RETURNING TO THE SEA. 



Weight. 

 fts. 



18-59. 



No. 21 Feb. 14 ........ 10 



No. 76 March 2 ........ 11 



No. 95 March 29 ...... 12 



RETAKEN ASCENDING THE 

 RIVER AS CLEAN FISH. 



1859. Weight 



fts. 



No. 21 Aug. 18 17 



No. 76 Aug. 18 17 



No. 95 Aug. 12 19 



These figures speak for themselves, and show the folly 

 of destroying, in a comparatively worthless condition, fish 



a maggot, as, according to Dr. Fleming, it never changes its state, or 

 becomes a fly. The most singular species of parasite to which Salmon 

 are subject is the Lamprey or Stone-sucker, which in several in- 

 stances, recently reported, has been found attached to them, having 

 bored a deep hole through the skin. 



