FISHES OF ARCTIC ALASKA. 



495 



Eiver. Oar specimens show. quite a range of variation in the number of gill rakers 

 and fin rays, given in the accompanying table. One of the specimens from the mouth 

 of the Mackenzie is the only one that shows perfectly the black markings on the 

 dorsal, as given in the figure of a similar sea-run individual from northern Alaska. 

 ( Whiteflshes of America. Eeport of U. S. Commissioner of Fish and Fisheries, 1894. 

 Plate 23; also same plate in Cruise of steamer Gorwin.) In addition to this it has a 

 few small, round black spots on top of the head and four or five similar spots on 

 adipose fin. All of the specimens have the articulation of mandible on a vertical with 

 center of eye. The diameter of eye equals the interorbital width and is greater than 

 length of snout. 



a No. 46. 

 5. Argyrosomus lucidus (Richardson). 



We obtained two specimens of this species in salt water off Herschel Islai;id. 

 They are undoubtedly identical with the species found in Great Bear Lake and Eiver. 

 We have compared them with two specimens from Great Bear Eiver. One of our 

 specimens has a larger number of scales than the other, but it is not a larger varia- 

 tion than may be expected within a species of this family. 



Besides the fin formula we give a few measurements not included in Jordan and 

 Evermann's otherwise full description: Longest dorsal ray, IJ in head; longest anal 

 ray, 2^ in head; pectorals reach less than halfway to origin of ventrals, or IJ in head; 

 ventrals reach less than halfway to vent, or 1§ in head; ventral scale a little over 

 half length of fin ; articulation of mandible with quadrate bone on a vertical with 

 posterior margin of eye. Length of each specimen, 16 inches. 



6. Argyrosomus alascanus Soofield, new species. (Plate XLII. ) 



Head, 4^ ; depth, about 4 ; dorsal, 12 ; anal, 12 ; scales, 10, 83, 9. Eye a little shorter 

 than snout, 5 in head, IJ in interorbital space. Head wedge-shaped, the upper and 

 lower profiles straight and meeting with a sharp angle at the snout. Viewed from 

 above the snout is blunt, almost square, with the narrow, pale, rounded tip of the 



