270 SILURIDjE. 



4. Aspredo nematophorus. 



Platystacus nematophorus, Bleek. in Compt. Rend. Acad. Sc. Amsterd. 

 1862, xiv. p. 371. 



B. 5. D. 5. A. 57. P. 1/7. V. 6. 



Closely allied to A. cotylophorus. 



Upper jaw spatulate, projecting beyond the lower ; barbels six, as 

 in that species. Upper part of the snout smooth ; eye very small. 

 The length of the head, to the gill-opening, is one-tenth of the total 

 (with the caudal fin)-. The first dorsal ray is produced into a fila- 

 ment ; the outer caudal rays not prolonged. Light brownish, mar- 

 bled with dark brown. 



Surinam. 



The typical specimen is in the Leyden Museum. 



5. Asnredo filamentostui. 

 Cuv. 8r Val. xv. p. 437. pi. 460. 



D. 5. A. 50. P. 1/8. V. 6. 

 Upper jaw rather pointed ; two maxillary barbels on each side, 

 me of which is very small, and attached to the base of the principal 

 one ; the latter extends to the gill- opening. A series of fine barbels 

 along each side of the sternal and abdominal regions. No spines on 

 the snout ; eye very small. The first dorsal ray is produced into a 

 very long filament. The hinder anal rays and the caudal fin black. 



Guianas. 

 a. Adult. Demerara. Purchased of Mr. Scrivener. 



6. Aspredo tibicen. 

 Aspredo tibicen (Temminck), Cuv. Sf Val. xv. p. 438. 

 D. 5. A. 58. P. 1/8. V. 6. 



Upper jaw rather pointed, and projecting beyond the lower. Two 

 maxillary barbels on each side, one of which is small and attached 

 to the base of the principal one ; the latter extends to the gill-open- 

 ing and is dilated into a broad membrane at its base. The lower 

 side of the head with rather numerous minute barbels arranged in 

 four longitudinal series, the middle of which extend backwards over 

 the sternal region. A transverse series of four small recurved spines 

 on the upper side of the snout, two of them belonging to the ethmoid, 

 and two to the nasal bones ; eye very small. Each jaw with a con- 

 tinuous cross-band of villiform teeth. The length of. the head, to 

 the end of the occipital process, is one-fifth of the total (the caudal 

 fin included). The first dorsal ray is considerably prolonged. Back 

 with large brown spots ; anal black, with the anterior portion white. 



British and Dutch Guianas. 



a-b. Adult. British Guiana. Presented by Sir R. Schomburgk. 

 e. Adult. British Guiana. From Mr. Snellgrove's Collection. 

 d-e. Young. Presented by the Royal College of Surgeons. 



