5Q T)R. A. GTJNTHER ON THE BRITISH CHARRS. [Feb. 11, 



ridge and tlie lateral series of pores scarcely visible. Snout ratber 

 depressed, conical, with the lower jaw slightly curved upwards and 

 overreaching the upper. The nostrils are situated midway between 

 eyeball and end of the snout ; the anterior is round, open, surrounded 

 by a membrane, which posteriorly is developed into a small flap, 

 nearly entirely covering the smaller, oblong, posterior nostril. By 

 this character alone the Torgoch may be distinguished from the 

 Charr and Freshwater Herring. The maxillary extends to (or scarcely 

 beyond) the vertical from the posterior margin of the eye, and is 

 armed with 19-21 teeth of moderate size ; six or seven teeth in each 

 intermaxillary, seventeen in each mandible ; seven teeth On the vomer 

 form two sides of a triangle, the point of which is directed back- 

 wards ; fifteen teeth on each palatine, five pairs on the tongue. The 

 suboperculum is produced backwards, covering the triangular por- 

 tion of the humerus above the root of the pectoral, and being in 

 immediate contact with the latter ; the vertical width of the sub- 

 operculum is one-half, or rather less than one-half, of that of the 

 operculum. Only three branchiostegals are exposed in a lateral 

 view of the fish, the others being situated at the lower side of the 

 head. The lower branch of the outer branchial arch is provided 

 with thirteen lanceolate straight gill-rakers ; the Iqpgest is somewhat 

 less than two lines long in the specimen described. 



D. 13(14). A. 12(11). P. 12 (13). V. 9. 



The origin of the dorsal fin is somewhat nearer to the snout than 

 to the root of the caudal ; the length of its base is not much less 

 than its height. The fifth and sixth rays form the rounded top of 

 the fin. The first ray is rudimentary, the second half as long as the 

 third, the third half as long as the fourth, the fourth simple, five- 

 sixths of the fifth, which is branched, the sixth the longest, the last 

 split to the base. The length of the base of the dorsal is contained 

 once and a third in its distance from the adipous fin. 



The Origin of the anal fin is exactly in the middle between the 

 root of the caudal and that of the outer ventral ray ; the length of 

 its base is less than that of the dorsal, and not much less than its 

 height. The four anterior rays are enveloped in a common mem- 

 brane ; the fourth and fifth rays form a rounded point ; and the lower 

 edge of the fin is slightly emarginate. The first ray is short, the 

 second half as long as the third, the third three-fourths of the fourth, 

 the fourth simple, a little shorter than the fifth, which is the longest 

 and branched ; the last split to the base, its length being nearly one- 

 half of that of the fifth. 



Caudal fin emarginate, the length of a middle ray being a little 

 more than one-half of that of the outer ones, the length of which is 

 contained six times and a half in the total. Lobes slightly rounded. 



The base of the pectoral is overlapped by the gill-cover apparatus. 

 It extends nearly to the vertical from the origin of the dorsal, is 

 considerably shorter than the head, and three-fourths of the distance 

 between its root and that of the ventral. 



The ventral is inserted in the vertical from the eighth to eleventh. 



