132 CALIFORNIA ACADEMY OF SCIENCES. 



Width below the dorsal spine about equal to its depth, 

 tapering to the caudal peduncle. Head rather short and 

 broad, its width 1| in its length. Skin of the head very- 

 thin, the surface of the bones little if at all roughened; 

 snout flat and broad, its width at the angle of the mouth 

 2 in the head. Fontanels in the young three: 1, a 

 small round one at the base of the occipital process — 

 present in the largest specimen; 2, a small one be- 

 hind the orbital bridge — obliterated in the adult, and 3, 

 the usual one between the frontal bones. Occipital 

 process continued to half way to dorsal spine. Numer- 

 ous groups of pores about the head; a group behind the 

 posterior nasal opening, a larger group between the 

 middle of the eyes; a group above the posterior margin 

 of each eye and a group behind each of these; a group 

 behind the eye; one at the upper angle of the opercle 

 another near its lower angle, other groups below the eyo 

 and elsewhere. 



Eye in smallest specimen 1| in snout, 5 in head, 1| 

 in interorbital; in largest specimen 21 in snout, 6i in 

 head, 2 in interorbital. 



Maxillary barbel extending scarcely beyond the end of 

 the dorsal fin in the largest specimen, to its middle in 

 some of the smaller specimens; mental barbels reaching 

 to the base of the pectoral, postmentals to the middle of 

 the pectoral. 



Mouth wide terminal; in the largest specimen the 

 jaws are equal, in the smaller the upper jaw projects. 

 Teeth of the lower jaw as usual; those of the upper jaw 

 in a band of uniform depth, 7 times wider than deep, 

 interrupted in the middle. 



Gill membranes separated to below the angle of the 

 mouth; gill-rakers 2+7. 



Distance of the dorsal fin from tip of snout 3 in the 

 length; the fin not longer than high;'highest ray IJ-li 



