SEA TROUT— SALMON-TROUT, DESCRIPTION OF. 157 



beneath the middle or last third of the dorsal. The dorsal fin is comparatively small : 

 while the caudal is subject to considerable diversities of form, in fish at about 

 twenty inches long being almost square at its posterior extremity, or in some few 

 instances notched, while in still large examples it becomes convex,* as in what 

 would be termed " round-tails " in the north. Scales — fourteen or fifteen rows 

 in an oblique line from the hind edge of the adipose dorsal fin, downwards and 

 forwards to the lateral-lino. The scales in this species, more particularly in the 

 young, are somewhat deciduous, about twenty-four rows from the lateral-line to the 

 base of the ventral fin. Ca-cal appendages vary considerably in number : thus a 

 Tweed examplef possessed only 33, but in other respects resembled this race. In 

 those examined in the Teith this and last year I found from 47 to 50.J As 

 regards the number of vertebra? I bave found from 57 to 59+.» counted as 

 explained at p. 15, i.e. omitting the last in my enumeration. Colours — Black 

 bluish gray, becoming lighter on the sides and beneath, having a purplish gloss 

 when in the highest condition, but which takes on a muddy hue after having boon 

 some time in fresh water. Small black spots on those fresh from the salt water, 

 mostly of an X-shapc, exist along the gill-covers and upper two-thirds of the 

 body, or merely upon the upper half of the gill-covers, where they may be 

 surrounded by a light margin, whilo on the body they frequently are not seen 

 below the lateral-line. But when the fish is in rivers for breeding purposes these 

 spots are usually larger and more numerous, sometimes having a purplish tinge 

 or a purplish or reddish surrounding. But some are densely, otheis sparsely 

 spotted, with every intermediate variety. The dorsal fin light gray or even 

 straw-coloured, and may be destitute of spots, thickly or thinly covered by thorn. 

 Pectoral of a bluish lilac, often darkest externally. Caudal gray, or even dark 

 coloured, but usually dull straw-coloured in the adult. During the spawning 

 season the head of the male is of an olive brown, becoming black on the under 

 surface, and the body of a dingy gray or reddi.sh brown, while the female is of a 

 blackish gray : the adipose dorsal fin with from one to three black spots on its edge, 

 also the upper and lower margin of the caudal are usually orange. § Sea trout par 

 or orange-fins are marked almost similarly to the young of the salmon, but the dorsal 

 fin has generally a more distinct white upper edge anteriorly, with a blackish basal 

 band, which often passes along almost the entire extent of the upper fifth of the fin, 

 and similar to the colours .seen in the brook trout, while its adipose dorsal is tipped 

 with orange. In the grilse stage (see whitling, p. 159) the caudal is usually 

 blackish, II becoming lighter as it gets older, first in its basal portion, which is 

 straw-coloured, and this spreads to the remainder of the fin. 



* Fleming stated that the hind margin of the caudal fin in this species is nearly even, Jenyns 

 that it is forked, Yarrell that it is less forked at the same age as the salmon but becomes ulti- 

 mately stiuare at the end, Giinther that the caudal is square at eighteen or twenty inches, but 

 in rare cases emarginate even at 2.5 inches. 



t Mr. Brotherston, of Kelso, sent me in August, 1882, a specimen from the Tweed, termed 

 " bull trout," it was a female, with small ova, only two teeth remained on the hind margin of 

 the head of the vomer, its tail was almost square at its extremity, and it only possessed thirty- 

 three cajcal appendages. 



J In the British Museum Catalogue, vol. vi, we are told of this form " cmcal pylori 49-01, rarely 

 less " : while the following are the number of those appendages asserted to be present in 

 specimens in the collection : five males from Scotland gave 43, 45, 50, 52, 58; twelve females 

 4(5, 49, 49, 50, 51, 52, 54, 55, 59, 59, GO ; one from the Ouse 49 ; one from the Eden 49 ; and one 

 from Fordwieh 50 ; showing variations from 43 to 60. Those having less than 47 seem to be 

 considered hybrids ; of these there are three, as follows : 38, 38, 42, and three more stated to 

 possess from 36-46. 



§ Thompson alluded to one example which had a series of deep orange longitudinal stripes, 

 possibly a male m the breeding livery, hut I have never seen one in the rivers of this colour. It 

 has been suggested (see bull trout, p. 172) that some of these fish may be hybrids between the 

 ,?. trutta and S. salar. 



II Eespecting the number of vertical bars or bands, the so-called finger marks, the following 

 have been recorded by various ichthyologists in Great Britain. Pennant (1776) observed of the 

 samlet or par that " it is also marked from the back to the sides with six or seven large bluish 

 bars : but this is not a certain character, as the same is sometimes found in young trout " 

 (p. 305, pi. Ux, no. 148). Fleming (1828) remarked that "the Samlet or Par of Pennant is now 

 generally considered as the young of this species {S. trutta) or of the salmon " (p. 180). Parncll 

 (1838) described "the lateral-lino crossed with from eight to nine, and sometimes ten, transverse 



