the San Juan R'irer, Colombia. 167 



Caudal forked. Greyish ; a strong blackish stripe from 

 snout through eve to base of caudal fin ; posterior half of 

 each Luterradial membrane of dorsal dusky. 



Five specimens, 75 to 145 mm. in total length, from the 

 Rio Condoto (Spurrell) and the ELio Sipi (Palmer). 



This species is related to P. buckleyi, Bouleng., from the 

 Amazons of Ecuador, which has shorter barbels, a longer 

 adipose fin, a different coloration, &c. 



22. Pimelodella yrisea, Regan. 

 R. Sau Juan (Palmer). 



23. Rhamdia wagneri, Guuth. 

 R. Sau Juan (Palmer). 



Nannorhamdia, gen. nov. 



Intermediate between Rhamdia aud Naiutoglanis, differing 

 from the former in the absence of dorsal aud pectoral spines, 

 the vestigial occipital process, the more posterior position of 

 the dorsal fin, and the shorter anal fin ; from the latter in the 

 less depressed head, the eyes lateral and with free margins, 

 the dorsal fin above instead of behind the pelvics, the caudal 

 forked instead of truncate. 



24. Nannorhamdia spurreUii, sp. n. 



Depth of body 6 in the length, length of head 4i. 

 Diameter of eye 2 in length of snout, G in length of head, 

 li hi in terorbital width. Lower jaw the shorter. Maxillary 

 barbel extending to end of pectoral fin. Dorsal 7 ; origin i 

 as distant from end of snout as from base of caudal ; adipose 

 fin as long as its distance from dorsal. Anal 9. Pectoral \ 

 length of head, not reaching pelvics, which are inserted 

 below middle of dorsal and do not nearly reach anal. Vent 

 a short distance behind base of pelvics. Greyish ; a dusky 

 lateral stripe. 



A single specimen, 70 mm. in total length, from the 

 R. Condoto (Spurrell). 



25. Pseudopimelodus transmontanns, sp. n. 



Skin with papillae or filaments, which are always evident 

 above the pectorals. Depth of body \\ to 6 in the length, 



Length of head 3to3£. Head nearly as long as broad. 1 >i i- 

 nieter of eye 1,' to 18 in length of head, interoeular width 



