46. SALMONID^E - COREGONUS. 301 



494. Co airfteslfi Lc Suenr. Lake Herring; Cisco; Michigan Herring. 



Body elongate, compressed, not elevated. Head compressed, rather 

 pointed. Mouth rather large, the maxillary reaching about to the 

 middle of the pupil, about 3i in head; the mandible 2 in head. Pre- 

 orbital bone long and slender; suborbital broad; supraorbital nearly 

 as long as eye, about 4 times as long as broad. Eye 4-5 in head. 

 Gill-rakers very long and slender, as in dupea, as long as eye, 25-30 

 below the angle. Bluish black or greenish above; sides silvery; scales 

 with dark specks. Fins mostly pale, the lower dusky tinged. Head 

 4J; depth 4^. D. 10; A. 12; scales 8-75 to 90-7. L. 12 inches. Great 

 Lakes and northward to Alaska and Labrador; very abundant, usually 

 frequenting shallow waters. In numerous small lakes in Indiana and 

 Wisconsin (Geneva, Tippecanoe, Ocouomowoc, etc.) is the modified var. 

 sisco (Argyrosomus sisco Jordan, Amer. Nat. 1875, 130), which lives in 

 the deep waters, coming into shallower waters to spawn in December. 



(Coregonus artediJ-ie Snenr, Journ. Acatl. Nat. Sci. Phila. i, 231, 1818: Coregtmus clwpei- 

 f or mis Giinther, vi, 193, and of nearly all authors, but not Sal mo diqn'ij'nrinia of Mitch- 

 ill : Salrno (Cone/onus} harenrjus Richardson, Fauna Bor.-Atuer. iii, 210; Sal mo (Coreyo- 

 WMN) luddus Richardson, Fauna Bor.-Amer. iii, 207: Coreyonus lucidim Giinther, \i, 198: 

 Coreyonus harenyus Giiuther, vi, 199.) 



495. C. uigrrnpiDiMis (Gill) Jor. Blue-fin; Black-fat. 



Body stout, fusiform, compressed. Head stout. Month large, the 

 lower jaw projecting. Eye rather large, longer than snout, about 4 

 in head. Teeth very minute, but appreciable on prenraxillaries and 

 tongue. Gill-rakers very numerous, long and slender. Color dark 

 bluish above: sides silvery, with dark punctulations; fins all blue- 

 black. Head 4J ; depth 3$. I). 10; A. 12; scales 9-88-7. L. 18 

 inches. Deep waters of Lake Michigan ; locally abundant. Larger 

 'than most of the other Coregoni. Known at once by tbe black fins. 



(Argyroaomus 'iiir/ripinms (Gill, MSS.) Milner, Rept. U. S. Fish Corn. 1872-73, 87, 

 1375; Jordan, Man. Vert. 275.) 



Body short, deep, compressed, shad-like; curve of the back similar to that of the 

 belly; scales lar^c, notably larger forwards, rather closely imbricated, the 

 posterior margin little convex. (Allosomus Jordan.*) 



496. C. tssSli&ce Rich. Tullibce; "Mongrel White Fish". 



Body short, deep, compressed, shad-like, the dorsal and ventral 

 curves similar. Caudal peduncle short and deep. Head conic, com- 

 pressed, much as in C. nigri_pmnis. Mouth large, the rnaxillar}* as long 



'Jordan, Man. Vert. ed. 2, 1878, 331: type Corerjonus tulUbee Rich, (a/l/lo?, other, 

 different; dfc/./a, body.) 



