274 CALIFORNIA ACADEMY OF SCIENCES. 



g. Anal rays normal, 28 or fewer. 



h. V. 9 or 10. Pectoral spine not reaching beyond the tip of the 

 humeral process. Dorsal plate with a descending process behind; 

 fontanel oval; lower jaw projecting. Head about as wide as long. 

 Dorsal spine almost as long as the pectoral spine. Head 5; D. I, 

 6; A. 20; P. I, 6. (Cuv. & Val.) trachycorystes 217. 



hh. V. 6 or 7. Pectoral spine reaching beyond the tip of the 

 humeral process. Dorsal plate without a descending process. 

 i. D. I, 4-5. 



j. V. 6. Humeral process ascending more or less obliquely 

 backward. 



k. Humeral process extending beyond middle of pectoral 

 spine. 



I. A. 20; mental barbels scarcely reaching to the base of 

 the postmentals; head as wide as long. Eye 7 in the 

 head, 1| diameters from the rictus; maxillary barbels 

 reaching beyond postmentals to the base of the pectoral 

 spine. Dorsal spine thick, serrate in front, lower than 

 the following rays. Pectoral spine longer than the dor- 

 sal spine. Dark brown with elongate blackish spots; 

 ventral surface white, sometimes covered with brown 

 dots; all the fins more or less thickly spotted with brown. 

 Head 4. (Kner.) ceratophysus 218. 



II. A. 24-25; mental barbels extending beyond base of post- 

 mentals, If in head. Bones of the head coarsely granu- 

 lar, the occipital bone with three pore-bearing grooves 

 forming a /r-shaped figure. porosus 219. 



kk. Humeral process not reaching the middle of the pectoral 

 spine. A. 25-27. striatulus 220. 



jj. V. 7. Head coarsely granular; fontanel reduced to a small 

 round hole. Maxillary barbels reaching to the middle of the 

 pectoral spine. Eye less than the iuterorbital width. 

 Humeral process half as long as the pectoral spine. Dorsal 

 spine dentate in front, half as long as the pectoral spine. 

 Blackish above, brown below, lower parts of sides with dark 

 spots. Head 4; depth 5; D. I, 5; P. I, 6; A. 22-23. (Cope.) 



brevibarbm 221 . 

 . D. I, 6; V. 6. 



m. A. 22-24, rarely 25. galeatux, 222. 



mm. A. 28. Bones of the head scarcely granular; fontanel ovate; 

 maxillary barbels extending to the end of the pectoral: 

 mental barbels not quite half as long as the head. Humeral 

 process extending to the posterior third of the pectoral 

 spine. Dorsal spine shorter and more feeble than pectoral 

 spine, creuulated in front. Pectoral spine as long as lira.!. 

 Uniform dark brown. Head 5; P. I, 7. (Gunther.) 



robustus 223. 



