1'20 OSTAEIOPHTSI. 



J . Vomerine patclies of teeth contiiuious with the larger elul)-sliaped palatine patches ; 

 maxillary harbel extending to operculum or nearly to base of pectoral. 



Width of mouth slightly more than ^ the width of liead 6. asaimi/is. 



Width of mouth nearly j? the width of head 7. (juuteiualensis. 



2. Vomerine patches of teeth oblong or oval, continuous or subcon- 

 tinuous with the palatine jiatches, which are only a little larger 

 than the vomerine ones and of similar form ; maxillary barbel 

 extending beyond the base of pectoral 8. caric/esceits. 



B. Fontanel produced backwards into a feeble groove which does not 



reach the parieto-occipital ; occipital process twice as long as broad ; 



inner edge of pectoral spine weakly serrated ; anal of 21 or 22 rays . 9. lentiyinosus. 



C. Fontanel produced backwards into a groove which nearly or quite reaches the parieto- 



occipital ; inner edge of pectoral spine weakly or moderatelj^ serrated; anal fin of 14 

 to 20 rays. 



1. Occipital process subtriangular, much broader tlian long ; 9 to 12 gill-rakers on the 



lower part oE the anterior arch; adipose fin sliortcr than the dorsal. 

 Occipital process rounded posteriorly ; pritmaxillary baiul of teeth 44 times 



as long as broad 10. (juentheri. 



Occipital process with straight sides and truncate apex ; pnemaxillary hand oi' 



teeth 5 to 6 times as long as broad 11. seemani. 



2. Occipital process as long as broad ; 6 gill-rakers on the lower part of 



the anterior arch ; adipose tin a little longer than the dorsal . . 12. loiii/icephaJns. 



3. Occipital process 3 times as long as broad; 10 giU-rakers on the 



lower part of the anterior arch ; adipose fin as long as the dorsal . 13. jieniviaiius. 



1. Galeichthys dovii. 



Lcjitarws dowi, Gill, Proc. Ac. Pliilad. 1863, p. 170'. 



Arius alatus, Stcind. Sitzuugsb. Ak. Wien, Ixxii. 1876, p. 569, t. 6". 



Si'/ena.yns dowi, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1900, p. 2761 '. 



Hah. Pacific Coast fmm Panama to Ecuador ; 

 Panama 123. Ecuador '■''. 



Tills is the Pacific representative of G. hcrzhcnjii, BL, from Guiana and Brazil. 



2. Galeichthys troscheli. 



Sriades troscheli, Gill, Proc. Ac. Pliilad. 1863, p. 171 \ 



Arius troscheli, Giiiith. Cat. Fish. v. p. l.iO (1864) '. 



Arius braiidtii, Stcind. Sitzungsb. Ak. Wien, Ixxii. 1876, p. 571, t. 3'. 



Sri(cdichth.,/s troscheli, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1900, p. 2757 '. 



Deiitli of "body 5 in tlie leiio;tli, lenpith of liead 3|. Breadth of head ] t to li in its longtli, diameter of cvo 

 7 to 8|. Fontanel not produced backwards iuto a distinct groove ; occipital process with a weak keel, 

 broader thaa long, (he sides straight, the posterior edge emarginate ; dorsal shield sub-pentagonal, 

 emarginate posterioily, about as broad as long, its length in the median line i to 1 of the distance from 

 tip of snout to origin of dorsal fin. Width of mouth ij to if the wiilth of head ; pra-'maxillary hand of 



