508 NEW YORK STATE MUSEUM 



with very small scales, sometimes hardly visible; large scales 

 on opercles; dorsal origin at a distance from eye equal to length 

 of pectoral, base of spinous dorsal nearly equal to one third of 

 total length without caudal, fourth to seventh spines longest, 

 equal to snout and eye combined, last spine two thirds as long^ 

 as the first and equal to snout; base of second dorsal one half 

 as long as first, the longest ray twice as long as last ray and 

 equal to postorbital part of head; the caudal peduncle rather 

 long and slender, from end of second dorsal to end of scales 

 being nearly equal to the head; caudal fin slightly emarginate, 

 the middle rays three fourths as long as the external, and one 

 third of length of head; the anal origin at a distance from tip 

 of snout equaling twice the length of spinous dorsal base, the 

 anal base equal to postorbital length of head, the two spines 

 nearly equal, about one third as long as the head, the longest 

 ray (fifth) equal to one half the length of spinous dorsal base; the 

 ventral not far behind the base of the pectoral, its length about 

 one half the distance from its origin to origin of anal; pectoral 

 one fifth of total length to end of middle caudal rays; lateral 

 line straight, extending from eye to base of caudal fin; breast 

 naked; a series of enlarged caducous scales on median line of 

 Mly. D. XII to XY, 11 to 13; A. II, 8 to 10; Y. I, 5; P. 14. 

 Scales 9-65 to 80-17; vertebrae 19+23=42; pyloric cacea three. 



The sides are straw colored or greenish yellow, with dark 

 tessellations and marblings above and with about seven large 

 dark blotches, which are partly confluent; the fins are barred, 

 and there is a small spot at the base of the caudal. 



The black-sided darter, or blenny darter, is found in the Great 

 lakes region westward to Manitoba and southward to Missouri, 

 Indiana, Kentucky and Arkansas, being specially abundant in 

 the Ohio valley. The U. S. Fish Commission had it from Marsh 

 creek, Point Breeze. It prefers clear streams with gravelly bot- 

 toms and is more active in its habits than most of the other 

 darters, not concealing itself so closely under stones. It grows 

 to the length of 4 inches. As an aquarium fish it is unsurpassed 

 by any of its kindred, and its sudden and remarkable changes 



