244 Dr. A. Giinther on a 



25. Cynoglossus abbreviatus. Gray. 



26. Cynoglossus gracilis, sp. n. 

 D. 139. A. 106. V. 4. L. lat. 150. 



Three lateral lines on the left side. On the level of the end 

 of the abdominal cavity the upper line is separated from the 

 middle by 21 rows of scales, and the lower from the middle 

 by 24. One lateral line on the right side. Scales ctenoid on 

 both sides. One ventral united with the anal. Two nostrils — 

 one between the eyes, the other opposite to the lower margin 

 of the lower eye. Eyes extremely small, the upper not in 

 advance of the lower ; interorbital space much wider than the 

 orbit. Lips not fringed. The length of the snout is contained 

 twice and one third in that of the head. Angle of the mouth 

 a little nearer to the end of the snout than to the hind margin 

 of the gill-cover, below the eye. The rostral hook terminates 

 behind the symphysis of the mandible. Tail much tapering 

 behind. The height of the body is scarcely more than the 

 length of the head, which is one fifth of the total (without 

 caudal). Uniform light brownish ; basal half of the vertical 

 fins darker than the outer half. 



One specimen, 9 inches long, and several young ones. 



27. Silurus asotus, L. 



MACEONES, LlOCASSIS, and PSEUDOBAGRUS. 



In my systematic arrangement of the Siluroid fishes, I 

 refused to acknowledge the presence or absence of a thin 

 integument on the upper surface of the head as a generic 

 character, whilst I admitted Bleeker's generic divisions of 

 Liocassis, based on the absence of an orbital fold, and of 

 Pseudobagrus, based on the many-rayed anal fin. However, 

 the discovery of a few new forms shows that, also, the two 

 latter characters are quite useless for a generic arrangement of 

 the species, and that Liocassis and Pseudobagrus should not be 

 separated from Macrones. 



28. Macrones {Pseudobagrus) fulvidraco. 



Pimelodus fulvidraco, Richards. Ichth. Chin. p. 286. 



Silurus calvarius, Basilewsky. 



Pseudobagrus fiilvidraco, Gthr. Fish. v. p. 85. 



Pelteobagrus calvarius, Bleek. Ned. Tydschr. Dierk. 1864, p. 9. 



Numerous examples. 



29. Macrones (Pseudobagrus) tenuis, sp. n. 

 D. 1/7. A. 22. 

 Head smooth above, covered with a thin skin, but the occi- 



