DIPLESION 293 



slightly emarginate; anal II, 8 or 9; pectorals . 8 to .9 in head; ventral 

 spines and first 4 or 5 rays rather fleshy and often somewhat knobbed 

 at extremities; separation of ventrals less than their width at base. 

 Scales6-8, 57-61. 7-9[10or 11]; lateral line nearly straight and usually 

 complete, 1 or 2 pores occasionally lacking; cheeks naked or with a few 

 more or less embedded scales; opercles and nape scaled; breast naked; 

 belly with ordinary scales. 



This beautiful and peculiar species, distinguishable at a glance by 

 its remarkable head, large prominent eyes, and small inferior mouth, 

 "giving it a decidedly frog-like profile," and by the green or olive 

 zigzag markings on the back, is, in its breeding dress, one of 

 the most beautiful of all fresh-water fishes. 'The dorsal fins be- 

 come bright grass-green, with a scarlet band at the base; the broad 

 anal has a tinge of the deepest emerald; while every spot and line 

 upon the side has turned from an undefined olive to a deep, rich 

 green, scarcely found elsewhere in the animal world except on the 

 backs of frogs. The same tint flashes out on the branching rays of 

 the caudal fin, and may be faintly seen struggling through the white 

 on the belly. The blotches nearest the middle of the back become 

 jet-black, and thickly sprinkled everywhere are little shiny spots of a 

 clear bronze-orange."* 



This darter has an almost inexplicable distribution in Illinois, 

 if we may judge by our collections of it. Taken by us in thirty-six 

 localities on the smaller streams of the Wabash system in this state, 

 it has not once occurred elsewheref in all our sixteen hundred collec- 

 tions, although it has been once taken from the DesPlaines at Joliet, 

 by J. H. Ferris, as reported by Fowler in 1906. | Its general dis- 

 tribution is not such as to suggest so limited a range in Illinois, occur- 

 ring, as it does, from Lakes Ontario and Erie to Pennsylvania, North 

 Carolina, and the lower Alabama basin, and thence to South Dakota, 

 Kansas, and Missouri, and the Red River in Arkansas. It is gener- 

 ally distributed throughout Indiana, as shown by the details of the 

 list of Professor Hay, who reports it as abundant in all suitable 

 streams. This is one of the groups of species occurring, in Illinois, 

 only or mainly in the Wabash drainage, specially discussed in our 

 introductory chapter on geographical distribution. It is found in 



*Jordan and Copeland, American Naturalist, Vol. X., p. 339. 



tThe indication of its presence at Chicago given on Map VII. of an article on the 

 local distribution of darters (Bull. 111. State Lab. Nat. Hist., Vol. VII., Art. VIII.) 

 published by the senior author in April, 1907, is due to a clerical error in transferring 

 a record based on the preservation of specimens from collections on exhibition at 

 the World's Fair in 1893. 



|"Some New and Little Known Percoid Fishes." Proc. Acad. Nat. Sci. Phila., 

 Dec, 1906, p. 522. 



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