14 Synopsis of the Fresh Water Fishes, 



distance from the snout. The body is crossed at its place of 

 greatest depth bj fourteen rows of scales. 



The dorsal fin commences above the base of the opercular 

 spine ; the anal under the sixth spine of the dorsal. 



D. xviii. 7. A. xiv. 7. C. 16. Y. i. 5. P. 12. 



The ground color is whitish brown, striped with longitudinal 

 lines of dark brown running along the angles of each row of 

 scales. The bases of the vertical fins are purple ; the remain- 

 ing portions brownish white with numerous scattered black dots. 

 The ventrals are purple, dotted with black ; the pectorals white, 

 immaculate. Head dark brown, dotted with black. 



Only two specimens of this fish were obtained, one of which 

 was taken in the " Tranquil river," a small narrow stream, 

 three or four feet in depth, with a muddy bottom, and few or 

 no stones. The other was captured by Mr. John "Wilson, in the 

 " Arouco river," under similar circumstances, and in a place 

 where a number of the larger branches of trees clogged the 

 stream. Both were caught in company with Cychlasoma taenia, 

 and with species of Poecilurichthys hereafter described. 



Family. 

 GoBiD^, Cdv. 



Sub-family. 



GOBIN^, SWAINSON. 



Genus. 

 Ctenogobius, Gill. 



Body oblong, compressed, with the dorsal and abdominal 

 outline subrectilinear, gradually tapering to the caudal fin, 

 without any constriction of the tail. 



The scales with which the body is covered are moderate or 

 rather large, angular at the middle of their free borders, and 

 with those borders pectinated, the teeth generally decreasing 



