54 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY II. 



ESOCID^. 



39. ESOX KOBILIOR, Thompson. 



? Esox masquinongy, Mitciiill, "Mirror, 18-24, 297 " (not there!).* 



? Esox estor, Richaudsox, Fauna Boreali-Americaua, iii, 1836, p. 127; and of sev^eral 



antbors (not of Le Sueur, Journ. Acad. Nat. Sci. i, 1818, 413). 

 Esox nobilior, Thompson, Proc. Bost. Soc. Nat. Hist, iii, 1850, 163, 173, 305 ; and of 



recent writers p;enerally. 



It is not quite clear why Dr. Mitchill's name for this species should 

 be set aside. Giinther remarks (Cat. Fishes Br. Mus. 1866, vi, 227), 

 " Mitchill has counted seventeen anal rays, and therefore it is probable 

 that his typical specimens belonged to this species {E. lucius) and not 

 to E. estor {nobilior), and rejects Mitchill's name on the supposition 

 that the number of rays in the Muskallunge is 20 or 21. But, in point 

 of fact, the number of anal rays is 16 to 18, usually one less than in E. In- 

 dus ", instead of 3 or 4 more. Moreover, Mitchill's specimen was about 

 4 feet in length and weighed 30 pounds, a size unusual for the Pike, 

 although specimens even larger are occasionally taken. Mitchill sup- 

 posed that the nsh in his possession was the Muskallunge ; he described 

 it, and named it on that supposition. 



The following description was taken from a specimen about 3 feet 

 long from Ecorse, Mich. (No. 10607, National Museum), and from three 

 smaller specimens from Lake Huron : — 



Depth 6 in length; head 3§; general form of E. lucins, the head 

 perhaps a trifle larger proportionally, 10 inches long in the larger speci- 

 men ; eye about midway in head. Interorbital space transversely con- 

 cave, with a prominent middle ridge ; maxillary reaching to opposite 

 middle of orbit. 



8caly part of cheeks about as wide as eye, beginning on a level with 

 the eye and running backward, its lower edge nearly parallel with the 

 profile. Scaly region of opercles similar. The amount of squamatioa 

 is variable within narrow limits. Eight rows of scales on cheeks and 

 about the same number on opercles. Scales on lateral line 150. 



Fin-radii: — B. 18-17; 17-17; 18-19; 17-17, in four specimens. D. 

 Ill, 17; III, 17 ; III, 17. Anal, II, 15; III, 14; III, 15. V. 12. 



Color dark gray ; sides with round dark spots of a grayish-black 

 hue, nearly the color of the back, on a groundcolor of grayish silvery; 



* A search through the files of the Mirror for Mitchill's description has proved un- 

 successful : it is not on the page cited by Dekay. 



