SOUTH AMERICAN NEMATOGNATHI. 225 



u. Superciliary edges much raised, the interorbital deeply concave; 

 coracoid bone striate, its process sharply gi-aniilar; a single plate 

 above and below immediately in front of the caudal fin; two high 

 smooth ridges on each side of the dorsal spine. Lat. 1. 24-25. 



asieri/rons 181. 



uu. Superciliary edges little raised, the interorbital nearly flat; pro- 

 cesses of the coracoid bones striate; caudal peduncle withoiit 

 plates above and below; four or five deep gi-ooves on each side of 

 the dorsal spine. Lat. 1. 29-30. hecheUi 182. 



tl. Dorsal spine grooved, not serrate; caudal truncate; lateral scutes 



each with a single large recurved hook. 



V. Entire lower surface of the clavicle and coracoid bones with 

 striate dermal ossification; maxillary barbel reaching posterior 

 margin of orbit; eye 3f in the head. If in the Interorbital. Hu- 

 meral process with a series of strong spines, reaching the vertical 

 from end of dorsal plate. Pectoral spine extending beyond the 

 ventrals; pale brown, the pectoral spine dark spotted. Head 3J; 

 depth 3J; D. I, 6; A. 12; P. I, 6; Lat. 1. 25. (Cope.) 



monitor 183. 



vv. Coracoid surface only with dermal ossification; mental barbels 

 reaching ti^J of coracoid process, maxillary to end of pectoral 

 spine; eye 3 in the head, 1 in the interorbital. Pectoral spine 

 extending past base of ventral fins. Brown above; a yellow band 

 along middle of sides bordered above with red, below with black; 

 belly white, purple below the pectoral; caudal fin with vertical 

 bars. Head 3 to middle of caudal. D. I, 6; A. 12; P. I, 4; Lat. 1. 

 26. (Cope.) nauticus 184. 



161. Doras dorsalis. 



Doras carhiatus Val. in Humb. Observ. Zool. ii, 184 (not Silurus 



carinatus L). 

 Doras dorsalis Cuv. & Val. xv, 284, 1840 (Cayenne); Kner, SB. Ak. 



Wien, xvii, 1855, Ichthyol. Beitr. 128 (Para Rio); Giinther, Cat. 



Pish. Brit. Mus. v, 205, 1864 (copied); Eigenm. & Eigenm.Proc. 



Cal. Acad. 2d Ser. i, 159, 1888 (Para). 

 Doras papilionatus Fillippi, Guer. Meuev. Eev. & Mag. Zool. 



167, 1853 (Amazons); Giinther, 1. c. (copied). 

 Doras lithogastcr Heckel, MS. in Kner, SB. Ak. Wien, xvii, 132, 



1855 (Forte do Eio Branco); Giinther, 1. c. (copied). 

 Lithodoras lithogasier Bleeker, Nederl. Tijd. Dierkunde, i, 15, 1863 



(name only). 

 Habitat: Para; Rio Negro and Cayenne. 



The characters assigned to papilionatus are not of suf- 

 ficient value to separate it from dorsalis. Doras litho- 

 gasier is probably the old of dorsalis. 

 15 



