ON THE ESOCES OP MIDDLE NORTH AMERICA. 



409 



basis of first dorsal ray three times to margin of preeoperculum, or a short distance in 

 front of it. 



Var. A. All the abdominal, and most of the lateral scales give vent to a tube like those 

 of the lateral line, at the bottom of a deep emargination. The head is contained four 

 times in the length to the end of the caudal fin. Color, with broad brown bars directed 

 obliquely forwards on the sides, or more numerous narrow black lines. 



Of this variety there are numerous specimens in Museum Academy, from the neigh- 

 borhood of Philadelphia, from Darby Creek, and the black lined form from White Clay 

 Creek, Chester County, procured by my friend Vincent Barnard, of Kennett Square. It 

 docs not inhabit the running waters, but may be seen at any time in the "cut offs" and 

 pools or dams, under the shelter of the broad leaves of the Nuphar advena, or among 

 the Pontederias and Potamogetons. It will seek out such situations through the most 

 insignificant outlets and rills, where it would seem to be in constant danger of having its 

 retreat cut off. It docs not attain a large size. 



Var. B. Few or no tube-bearing scales, except those of the lateral line ; abdominals 

 entire ; length of head three and one-half times in length to end of caudal. Broad oblique 

 lateral bars. 



Four specimens from Michigan, described formerly as K oypho, and only differing from 

 Eastern specimens as above. I have thought best to erase the name cypho (hunchback), 

 as the feature it expresses is probably to a considerable extent the result of distortion. 



Esox umbrosus, Kirtland. 



Cleveland Annals Science, 1854, p. 79. Esox? Cope, Pr. A. N. Sci. Phila., 1865, 79 

 (Grosse Isle). 



In addition to characters given above, this species possesses the following : 



Branchiosteg. radii 12—14; anal 2—3. 12; scales 12—15, 113—122, 13—15. Ten to 

 twelve rows of scales on the cheek. 



Var. A. From basis caudal to opposite basis dorsal three times to between praeopercu- 

 lum and orbit, or to between posterior margins of orbits (in specimens from Kichmond, 

 Indiana) ; brown bars on the sides directed forwards below. 



Three specimens, one from Grosse Isle, near Detroit, one from Michigan City, la. 



This variety, or the preceding species, may be that referred to by Prof. Kirtland as the 

 E. fascialus, found in Ohio. 



Var. B. From basis caudal to opposite first dorsal ray three times in length to anterior 



VOL. XIII. — 52 



