53. PIMELODUS. 119 



longer. A blackish streak from the eye along the lateral line ; dorsal 

 fin with the usual whitish cross-band. 

 Brazil. 



a-b. Five inches long. Brazil. Presented by Lord Stuart. 



C. The occipital process does not extend on to the basal bone of the dorsal 

 spine ; body elongate. 

 1. American species. 

 a. Dorsal fin with six soft rays. 



a. The adipose fin is one-third, or more than one-third, of the total 

 length (without caudal). 

 aa. The maxillary barbels extend considerably beyond the origin 

 of the adipose fin. 



8. Pimelodus sebae. 



Seba, hi. pi. 29. fig. 5. 



Mystus, sp., Gronov. Mus. Ichth. i. p. 34. no. 83, and Zoophyl. p. 125. 



no. 384. 

 Pimelodus sebae, Cnv. ty Vat. xv. p. 169 ; Kner, Sitzgsber. Acad. Wiss. 



Wien, xxvi. p. 417; Hyrtl, Denkschr. Acad. Wiss. Wien, 1859, xvi. 



p. 16. 



D. 1/6. A. 12. P. 1/8. V. 6. Vert. 13/26. 



Head covered with a very thin skin above, or almost naked ; occi- 

 pital process triangular, much longer than broad, not reaching the 

 basal bone of the dorsal spine. Adipose fin very long, its length 

 being contained twice and a third in the total (without caudal) ; it 

 commences immediately behind the dorsal fin. Maxillary barbels 

 extending on to the caudal, the outer ones of the mandible nearly to 

 the ventral. 



The height of the body is a little less than the length of the head, 

 which is one-fifth of the total (without caudal) ; the lower jaw 

 scarcely shorter than the upper ; the band of intermaxillary teeth is 

 about eight times as broad as long. The diameter of the eye is one- 

 half of the width of the interorbital space. Dorsal fin with the spine 

 very feeble, as long as high, or, in young specimens, rather higher 

 than long. Pectoral spine serrated along both edges, as long as the 

 head without snout. Caudal fin cleft to the base. Coloration uni- 

 form , dorsal fin blackish, with a white band across the basal portion. 



South America. 

 a, b, c. Young. Demerara. Presented by Dr. Hancock. 



d. Half-grown. British Guiana. From the International Exhi- 



bition 1862. 



e. Adult : not good state. Brazils. Purchased of Mr. Frank. 



f. Adult. South America. Presented by Sir R. Schomburgk. 



9. Pimelodus mulleri. 



? Pimelodus musculus, Mull. $ Trosch. Hor. Ichth. iii. p. 4. 

 D. 1/6. A. 10-11. P. 1/9. V. 6. 

 Head covered with a very thin skin above ; occipital process tri- 



