160 



SALMONID^ OF BRITAIN. 



on this fish. No. 3 male, 8'2 inches long, csecal pylori 50 : length of head ^f in 

 the entire length. Few spots below the lateral-line. Dorsal fin spotted, its 

 upper-anterior corner black : pectoral very dark : caudal dark edged. No. 4, 8'1 

 inches long : csecal pylori 40 : length of head 4A in the entire length. Only a few 

 black spots below the lateral-line : dorsal fin spotted with black and having its 

 upper-anterior margin with a white edge : adipose dorsal edged with orange : 

 pectoral fin reddish except at its edge. Teeth as in No. 1. No. 5, female, 

 7'6 inches long: csecal pylori 60 : length of head 4j in the entire length. Upper- 

 anterior corner of dorsal fiu black margined with white. No. 6, 7'8 inches long : 

 csecal pylori 42 : length of head 6i in the entire length. No. 7, 7'5 inches long : 

 Ciecal pylori 43 : length of head 4|- in the entire length. No. 8 in colours was a 

 yellow trout, male, 8'8 inches long : csecal pylori 40 : length of head 5 in. the 

 entire length ; colours yellowish, having numerous large red spots surrounded by 

 a light edging : dorsal fin densely spotted, its upper-anterior comer with a black- 

 based white edging : caudal fin red edged. 



In the foregoing series (excluding No. 8), the colours of the fins graduated 

 towards those of the brook trout : the length of the head of a local example of 

 male brook trout was one-fifth of the entire length of the fish, whereas in these 

 whitlings it varied from 4|^ to 5i in the total : the lower limb of the preopercle in 

 all but one was very short, when the adipose or dead fin was orange the pectoral 

 was light coloured : and the anterior-superior margin of the back fin from being 

 nearly black in some had a white margin in others, while in two there was abso- 

 lutely no black spots at all on this fin. As to the vomerine teeth,* in all a row 

 was present along the hind margin of the head of that bone, and in a more or 

 less complete zig-zag line along its body (see fig. 29, no. 1, p. 156). The csecal 

 appendages averaged 53, but were of varying numbers from 40, 40, 42, 43, 46, 

 50, 60. In the one in which the vertebrse were examined, there were 68 -\- x. It 

 must be evident that in this series we have evidence of a gradual approach from 

 the sea to the river trout. 



Fig. 34. Head, natural size, of female Sewin or southern race. 



The race of sea trout generally considered as more exclusively our southern 

 and Irish onef has been subdivided by authors in accordance with its size, sex, 

 external appearance, and the number of teeth existing on the body of the vomer. 



* Parnell observed of tlie vomerine teeth that " they are from nine to twelve in number, and 

 in about one example out of twenty only three of these teeth are perceptible, and these confined 

 to the most anterior part " (p. 296). 



t Donovan, in his Tour in South Wales and Monmouthshire, drew attention to this form, which 

 he termed Sahno camhricus (for synonymy, see p. 150 ante), observing on its appearing on the sea 

 coast and in the rivers of Wales during the summer months, from May to September, and then 

 returning to the sea. 



In the Beport of the Commissioners appointed to inquire into the Salmon Fisheries of England 



