ETHEOSTOMA 307 



and anal almost plain white. Females and males in late-summer color 

 much lighter, fall specimens often suggesting Boleosoma nigrum. The 

 large size and peculiar shade of the rusty-brown to rusty-red blotches 

 will usually serve for the recognition of this species. Head 3 . 7 to 4, less 

 pointed than E. jessice, the muzzle rather blunt, scarcely decurved; width 

 of head 1 . 8 to 2 . 1 in its length; interorbital space not much wider than 

 half of eye, 6 to 8 in head; eye nearly round, -3 .3 to 4. 4 in head; mouth 

 rather small, nearly horizontal, subterminal, maxillary reaching to front 

 of orbit; cleft 3 . 6 to 4; lower jaw included; gill-membranes scarcely con- 

 nected, distance from muzzle to angle usually less than 1 . 1 times that 

 to back of orbit. Dorsal fin VIII-XI, 9 or 11 ; spinous and soft portions 

 separated by a space somewhat greater than diameter of eye; height of 

 first dorsal 2 . 1 to 2 . 7 in head, second 1 . 8 to 2 (height of "first 68 to 94 

 per cent, of second) ; caudal truncate or very faintly lunate; anal II (occa- 

 sionally I), 6 to 8 (usually 7) ; pectorals 1 .2 to 1 .4 in head; separation of 

 ventrals always less than half, sometimes only J, their width at base. 

 Scales 5 or 6 (occasionally 7), 55-60, 7-9 [10-12], lateral line somewhat 

 flexed upward anteriorly*, as in E. Jessies; about 25 pores usually lack- 

 ing; cheeks, opercles, and nape fully scaled; breast naked; belly covered 

 with ordinary scales. 



A rare species in Illinois, taken by us from eight localities, all in 

 northern Illinois except one from Johnson county. The following 

 'are the recorded places: Pistakee Lake, in McHenry county; Wolf 

 Lake, South Chicago ; Senachwine Lake, Henry county ; Rock River 

 at Milan, Rock Island county ; Green River, near Geneseo, in Henry 

 county; Pecunsagan creek, near Utica, La Salle county; Illinois 

 River, at Ottawa; and Dutchman's creek, near Vienna, Johnson 

 county. 



Its known general range is northward at least as far as Qu'Ap- 

 pelle River in Assiniboia, westward to Valentine, Neb., and south- 

 ward to Arkansas. 



ETHEOSTOMA JESSLE (Jordan & Brayton) 



Jordan & Brayton, 1877, Jordan's Man. Vert., 227 (Poecilichthys) . 

 J. & G., 518 (Poecilichthys); M. V., 133; B., I, 72; J. & E., I, 1084; Forbes, in J., 

 41 (Poecilichthys asprigenis) ; F., 64 (asprigene); L., 29. 



Length ordinarily a little less than two inches, though specimens 

 are occasionally found 2\ inches; depth 4.8 td 5.4 in length; body as a 

 rule considerably compressed, its greatest width about f of its greatest 

 depth; dorsal and ventral outlines usually about equally arched, giving 

 the fish a symmetrical, bass-like form, which appearance is aided by 



*In E. jessice and iomcE the lateral line is nearly parallel with the line of the back. 

 The difference between these species and Boleichthy-s fusijormis in this feature 

 seems to be in the closeness of lateral line to the back at its highest point rather 

 than in the matter of parallelism. 



