44 CALIFORNIA ACADEMY OF SCIENCES. 



i. Eye 9 in the inter orbital; dorsal plate ernargiiiate be- 

 hind, as wide as the cranium behind eye; granulations 

 not extending forward to eyes; opercle and humeral pro- 

 cess striate, not granular; dorsal and pectoral spines 

 granular, moderately serrate. Upper jaw little longer; 

 palatine bands of teeth oval. Maxillary barbel extend- 

 ing to middle of pectoral. Ventral shorter than pectoral 

 fins; adipose one-third less than anal fin. Upper caudal 

 lobe little the longer. D. I. 7; A. 18.* (Cuv. & Val.) 



flavescens 25. 



ii. Eye 6-7 in the interorbital; dorsal plate half as wide as 

 the skull behind the eye, pointed in front, entering the 

 broad, short occipital process; surface of the bones 

 striate rather than granulate. Maxillary barbels reach- 

 ing tips of ventrals. D. I, 6; A. 21. t (Cuv. & "Val.) 



temminckianus 26. 



hh. Eye 5 or less in the interocular space. 

 j. Maxillary barbels reaching middle or end of dorsal fin. 

 Dorsal plate as wide as long, its surface pitted. Granu- 

 lations of the head extending to above middle of cheeks. 

 An elongate patch of teeth behind each palatine patch. 

 Upper caudal Iobe3f in the length. Head 3^. 



emphysetus 27. 



jj. Maxillary barbels not reaching beyond base of pectoral. 

 Dorsal plate longer than wide, its surface granular. 

 Granulations of the head extending to above the eye. 

 No pterygoid teeth. Upper caudal lobe 5 in the length. 

 Head 3^. brandtiZS. 



f/<j. Dorsal plate notched in front, receiving the point of occi- 

 pital process. 



k. Eye midway between snout and preopercle; occipital pro- 

 cess twice as long as broad, its tip mucronate, correspond- 

 ing to a notch in the dorsal plate; top of head granulated 

 to front of eyes; opercle granulated superiorly; humeral 

 process as long as high, strongly granulated. Veutrals as 

 long as pectorals. Maxillary barbels not reaching beyond 

 middle of pectorals? D. I, 7; A. 184 (Cuv. & Val.) 



mesops 29. 

 kk. Eye nearer snout than to preopercle. 



I. Jaws subequal; occipital process broader than long, 

 mucronate at tip; dorsal plate large, butterfly-shaped; 

 opercle striate. Eye 1 in snout. proops 30. 



*Based on a specimen .81 in. long. 

 IBased on a specimen .20 m. long. 

 JBased on a specimen .43 rn. long. 



