of the Fishery Board for Scotland. 



Ill 



APPENDIX VIII. 



NOTE ON THE TAY BULL-TROUT, WITH AN ANALYSIS 

 OF ITS FLESH. 



By W. L. C ALDER WOOD. 



In an .attempt to elucidate the true nature of bull-trout in the Tay 

 and other localities,* I have already stated my reasons for believing that 

 the fish known as the bull-trout in the Tay District is in reality a 

 salmon which has undergone a modification of a more or less temporary 

 and superficial kind. 



The flesh of the bull-trout is usually paler and rather yellower than 

 the well-known salmon colour, and is regarded as inferior for the table. 

 On this account the fish does not command so high a price in the 

 market. Public taste in salmon seems to insist upon the rich colour of 

 the flesh, as is well shown by the experience of the salmon canners on 

 the Pacific Coast of North America. A considerable variety of salmon 

 of pale and even parti-coloured flesh is, I understand, now canned, as 

 well as the vast quantities of red -fleshed Sockeye in the Fraser River 

 and Columbia River Districts ; but for European export, and especially 

 for consumption in the United Kingdom, only red-fleshed fish can be 

 used. All pale-fleshed fish, though they may be equally palatable and 

 perhaps equally nourishing, find no sale here. 



In order to test the value of the Tay bull-trout's flesh, Dr. Noel 

 Paton very kindly agreed to have an analysis of a few examples made. 

 This was done by his chemical assistant, Mr. Paterson. Three typical 

 specimens were therefore selected and sent to the laboratory of the 

 Royal College of Physicians, Edinburgh. All were fresh run females, 

 with sea lice attached, and were caught by net in the estuary of the 

 Tay on 17th August, 1903. Particulars of these fish are as follows : — 



No. I. 



Length, 34" (86-4 cm.). 



Depth, 8" (20-3 cm.) ; Caudal Ped., 57 cm. 



Weight, 18 lbs. 5 oz. 



Fins, D. 13, P. 13. 



Length of head, 16*5 cm. 



Length between eye and edge of gill cover, 9*5. 

 Gills, right with maggots, left without maggots.t 

 Teeth, 2 on head of vomer. 



Scales, 12 on right, 11 on left (from posterior of adipose fin to lat. line). 

 Spots below lat. line extending backwards as far as level of post, border 

 of D. fin. 



Viscera — Pyloric appendages loaded with fat. 

 Gall bladder much distended. 

 Stomach empty ; intestine with yellow mucus. 

 Liver normal. 

 Flesh pale in colour. 



* " The Bull Trout of the Tay and of Tweed." Proc. Roy. Soc. Ed., xxv., Part 

 I., p. 27. 



t The so-called " Maggots " are the crustacean parasite Lemeopoda salmonia* 



