80 CALIFORNIA ACADEMY OF SCIENCES. 



flat and smooth; posterior portion of the head finely and 

 sparsely granular; opercle and humeral process smooth; 

 occipital process about as long as broad, unusually 

 sharply keeled. Fontanel extending to above the pos- 

 terior part of the orbit, continued as a deep groove to 

 base of occipital process. 



Eye large, If in snout, 5h in head, 2 in the interor- 

 bital, 2f-3 in the interocular. 



Maxillary barbels extending to the pectoral pore, post- 

 mentals at least to the gill opening, mental about three- 

 fifths as long as the postmental barbels. 



Snout blunt, decurved; upper jaw a little ^ ^ 



produced. Teeth all villiform, those on the ^^^^^^TTV-/ 

 vomer forming two small, separate, ovate ^y \\ 

 patches, which are contiguous to the twice ^7 

 or thrice as large palatine patches. 



Gill-membranes forming a fold across the isthmus. 

 Gill-rakers 6+9. 



Pectoral pore large; vertical series of pores present. 



Distance of dorsal spine from tip of snout 2|-2| in 

 the length; the spine of the dorsal and pectoral fins 

 granular on the basal half of their outer margin; almost 

 the entire inner margins serrate, the spines of equal 

 length, IJ in head. 



Distance of adipose fin from the dorsal 3| in the 

 length; the adipose more than half as long as the dorsal 

 fin, its posterior margin free. 



Caudal deeply forked, the uj)per lobe longer, some- 

 what falcate, 3|-4 in the length. 



Anal fin about as long as high, deeply emarginate, 

 its highest ray 2| in the head. 



Ventral fins not reaching to the anal, 2 in the head. 



Dorsal surface dark blue with metallic lustre, becoming 

 silvery below; lower caudal lobe dusky; basal half of the 

 inner surface of the paired fins black. 



Head 3|-3|; depth 5*-5|; D. I, 7; A. 18. 



