SALMONID^E. 119 



possibility of any error of identification occurring. In the Lake districts they 

 average from 1^ to over 21b. but they have been obtained many pounds heavier 

 in weight. 



4. Salmo fontinalis, Plate CXX, figs. 1, 2. 



Salmo fontinalis, Mitchell, Trans. Lit. and Phil. Soc. New York, i, p. 435 ; 

 Richards. Faun. Bor.-Amer. iii, p. 176, pi. lxxxiii, f. 1 and pi. lxxxvii, f. 2; Storer, 

 Report Fish. Mass. p. 106 ; Kirtl. Report, Zool. Ohio, p. 169, and Boston Journ. 

 Nat. Hist. 1843, pt. iv, p. 305, pi. xiv, f. 2 ; DeKay, Fauna New York. Fish, 

 p. 235, pi. xxxviii, f. 120 ; Ayres, Boston Journ. Nat. Hist, iv, 1843, p. 273 ; Cuv. 

 and Val. xxi, p. 266 ; Bingelow, Bost. Journ. Nat. Hist, vi, 1850, p. 49 ; Giinther, 

 Catal. vi, p. 152. 



Salmo hoodii, Richards. 1. c. iii, p. 173, desc. part. (spec, from River Mingan). 



Salmo nigrescens, Ratin. Ichth. Ohiens. p. 45. 



Baione enjthrogaster, DeKay, Faun. New York. Fish. p. 236, pi. xxxix, f. 126. 



Hucho fontinalis, Giinther, Catal. vi, p. 152. 



B. x-xi, D. 12-13 (V) I 0, P. 12-13, V. 8-9, A. 10-11 ( y 3 9 -), C. 19, L. 1. 122- 

 140, L. tr. 36-50/51-63, Cose. pyl. 34, Vert. 59-62. 



Length of head 4t\ to 5f (4 J in a male), of caudal fin 6, height of body 4f to 5 

 in the total length. Eyes diameter of each from 4<\ to 5 or 5|- in the length of 

 the head, 1 to \\ diameters from the end of the snout, and from 1 to If apart. 

 Hind edge of preopercle regularly curved and with a very short but distinct 

 lower limb. Height of opercle equals twice its greatest width ; height of sub- 

 opercle equals half the length of its lower edge which, with its hind margin, forms 

 a regular curve. The form of the various opercular pieces in these fishes is liable 

 to great variation frequently due to an apparent arrest of development ; this is 

 also seen at Howietown among examples which have had gill-fever in their infancy, 

 and is considered to be one of its results. In one example the subopercle differs on 

 the two sides of the same fish. The maxilla reaches to beneath the hind edge of 

 the eye. Teeth 4 or 5 across the anterior portion of the vomer where that bone 

 joins the palatine arch but none along its body. In a single row along the palatines 

 and in the jaws. Fins the rayed dorsal commences slightly nearer to the end 

 of the snout than to the base of the caudal fin, its third or fourth ray is the longest 

 and somewhat exceeds the length of the base of the fin. Pectoral extends about 

 half-way (in some examples more, in others less) to the base of the ventral, 

 which latter is inserted below the centre of the rayed dorsal fin, laid flat it does 

 not quite reach the vent. Caudal forked in the young, but becoming square with 

 age, as seen in the trout. Scales 40 to 49 rows from the lateral-line to the base 

 of the ventral fin : 21 to 26 rows from the hind edge of the base of the adipose 

 dorsal fin downwards and forwards to the lateral-line ; from 185 to 235 rows pass 

 from the back to the lateral-line. Colours greenish along the back, becoming 

 lighter on the sides and beneath, the whole being beautifully shot with purple and 

 gold. Numerous round or oval spots along the back becoming fewer below the 

 lateral-line ; anteriorly from the head to the dorsal fin many coalesce. Red 

 spots above, on, and sometimes below the lateral-line. White edges with black 

 bases to the upper margin of the pectoral and the anterior edges of the ventral 

 and anal. Sinuous bands of black or rings on the dorsal fin : the upper and 

 lower edges of the caudal barred. During the breeding season, the lower surface 

 of the body of the male is frequently of an intense velvety black. 



Varieties. The following refers to an example 9 inches long, which was 

 hatched from eggs received from Lake Huron, and which lived some years in a 

 tank at the Westminster Aquarium. 



B. x, D. 13 (f), P. 11, V. 8, A. 10 (f), C. 19. 



Length of head 4|, of caudal fin 1\, length of body 5^ in the total length. 

 Eyes diameter 6 in the length of the head, If diameter from the end of the 

 snout and 2 diameters apart. Subopercle nearly twice as long as deep. Scales 

 43 rows from the lateral-line to the base of the ventral fin ; 24 from the hind edge 



