1. SALMO. 107 



taken from the upper end of the gill- opening to the angle of the 

 operculum is longer than a line from the latter point to the lower 

 anterior angle of the suboperculum. 



The distance of the origin of the dorsal fin from the occiput, if 

 measured behind that fin, reaches to the hinder third of the dis- 

 tance between the adipose and the root of the caudal. The dorsal 

 fin is as long as high, and composed of fourteen rays, the three 

 anterior ones being rudimentary and enveloped in the skin ; the 

 fourth ray is simple, and nearly as long as the fifth and sixth rays, 

 which are equal and the longest of the fin, the fifth being the first 

 branched ray ; the last ray is cleft to the base. The anal fin is 

 one-fourth higher than long, and composed of twelve rays, the 

 first three being rudimentary and enveloped in the skin, the 

 fourth simple, nearly as long as the fifth, which is branched and 

 the longest of the fin ; the last ray is split to the base. Pectoral 

 longer than the postorbital portion of the head. Ventral shorter, 

 its length being a little more than half the distance of its root 

 from the anal ; its outer ray is in the vertical from the tenth of 

 the dorsal. Posterior margin of caudal truncate, with the lobes 

 acutely pointed. 



There are about 120 transverse series of scales, counted immedi- 

 ately above the lateral line ; the transverse series descending ob- 

 liquely backwards from the origin of the dorsal fin to the lateral 

 line contains twenty-six scales, and there are twenty-two or twenty- 

 three longitudinal series between the lateral line and the root of the 

 ventral. The transverse series descending forwards from behind 

 the adipose fin contains fifteen scales : all the scales are very thin, 

 irregularly rounded behind. 



Bright silvery, greenish on the baek ; sides with a few black 

 X-shaped spots. Gill-cover and upper side of the head with round 

 black spots. Dorsal fin with a few black specks ; the other fins 

 immaculate. 



25. Salmo hardiuii. 



Deijefors-Lax. 



? Salmo lacustris, Niks. SJcand. Faun. Fisk. p. 404. 



Salmo salar, var. lacustris, Hardin, in Of vers. Vetensk. Akad. Forhandl. 



18G2, (1861) p. 382. 

 Silfv'er-lax, Lloyd, Scand. Advent, i. p. 116. 

 PVetterns Silfver-Iax, Widegren, in Of vers. Vetensk. Akad. Forhandl. 



1863, (1862) taf. G. tig. 1. 



D.15. A. 12. P. 14. V. 9-10. L. lat. 122. L. transv. 22/30. 

 The depth of the head at the occiput equals the length of its post- 

 orbital portion ; operculum rather higher than long ; the posterior 

 point of junction of operculum and suboperculum is a little nearer to ' 

 the lower anterior angle of the suboperculum than to the upper end 

 of the gill-opening. Praeopcrculum with a very distinct inferior 

 limb, which is more than half as long as the posterior. Snout rather 

 pointed ; maxillary longer than the snout, strong, extending to below 

 the posterior margin of the orbit (in specimens 23 inches long). The 



