474 DK. GUNTHEE ON THE FISHES OF CENTKAL AMERICA. 



its length being equal to, or a little less than, that of the head. The anal fin terminates 

 behind the adipose fin, and its last rays do not extend to the base of the caudal. Axil 

 of tlie pectoral with a very distinct porus mucosus. The pectoral spine is serrated 

 interiorly, sometimes a little longer, sometimes a little shorter, but always rather stronger 

 than that of the dorsal fin. Pectoral fin longer than ventral, two-thirds or three-fifths 

 of tlie length of tlie head. The ventral extends to the origin of the anal. Ujjper parts 

 brownisli, with steel-blue reflexions ; lower parts silvery, with a reddish tinge. 



Three examples were collected by Mr. Salvin in the Rio Usuraacinta ; the largest is 

 15 inches long. 



205. PiMELODUS WAGNERI. 

 Piiiivlodus cinerascens, Kncr & Steindachner, Abhandl. bayer. Akad. x. p. 49 (not Gthr.). 



D. 1/6. A. 11-12. 



Head covered with soft skin above. Adipose fin one-third of the total length (without 

 caudal). The maxillary barbels extend beyond the root of tlie ventrals ; the outer ones 

 of the mandible dt) not quite reach the base of the pectorals. The length of the head 

 is contained from five times and two-fifths to five times and seven-eighths in the total 

 (with the caudal), the height of the body seven times and one-third, or seven times and 

 one-half. Upper jaw projecting beyond the lower. The eye is equidistant from the 

 end of the snout and from that of the gill-cover ; its diameter is one-seventh or one- 

 eighth of the length of the head, and contained twice and two-thirds or twice and 

 thi-ee-fourths in the width of the interorbital space. Dorsal fin witli the spine very 

 feeble, as high as long. Pectoral fin two-tliirds as long as head. Porus axillaris 

 small. Coloration uniform, a darker streak along the lateral line ; dorsal fin with the 

 usual whitish cross band, and sometimes with a large round black spot between the 

 last two rays. 



Pacific and Atlantic rivers of Panama. 



The complete diagnosis of P. cinerascens (Gthr.), accompanied by a most accurate 

 figure, ])roves at once that the species discovered by Ilr. "Wagner is distinct from it. It 

 appears to be nearest to P. godmanni . 



206. PiMELODUS MANAGUENSIS. ' 



D. 1/6. A. 14-15. P. 1/9. 

 Head covered with soft skin above ; occipital process styliform, not extending to the 

 basal bone of the dorsal spine. Adipose fin very long, rather more than one-third of 

 the total length (without caudal) ; its distance from the dorsal is equal to the length of 

 the base of the latter. The maxillary barbels are rather short, extending nearly to the 

 base of the dorsal fin, the outer ones of the mandibles reach beyond the root of tlie 

 pectoral. The height of the body is contained six times in the t(jtal length (without 



