proci-:euings of united states national museum, 329 



the ni)per surface. A backward-directed spine on each preorbital. 

 Nostrils in a depression on each side of the snout. Lower Jaw received 

 within the upper both on front and sides. Jaws, vomer, and pahitines 

 armed with iriiiuite, sharp, closely set teeth. 



JNIaxillary almost entirely concealed by the free edge of the pre-orbital 

 when the mouth is closed. Two minute barbels at each angle of mouth. 

 Orbit large, almost (Mrcular, occupying far the larger portion (►f the 

 height of the liead, the upper margin of the pupil touching a line drawn 

 from tlic upper part of the snout to the occiput. 



Gill-membranes attached to a broad isthmus; branchiostegals seven. 



Pectoral shorter than head, broadly rounded on lower margin, and 

 composed of fourteen simple rays. 



Ventrals inserted posterior to the insertion of the pectorals, close to- 

 gether, consisting of a spine and two unbranched rays. 



Vent a conspicuous elliptical opening, situated at about the middle 

 of the length of the ventrals. 



First dorsal of four spines, the second longest, the fourth shortest, the 

 third slightly longer than the first; its base occupying the posterior 

 portion of the seventh, and the whole of the eighth and ninth series of 

 plates. 



Second dorsal of six unbranched rays, the second slightly longer than 

 the first; its base occupying the fifteenth to the nineteenth series of 

 plates, inclusive. 



Anal of six rays, opposite and similar to the soft dorsal. 



Caudal elongate, rounded on posterior margin, and consisting of 

 eleven unbranched rays. Fin-membranes delicate. 



Thirty-five to thirty-seven series of plates from occiput to base of 

 caudal, each series strongly keeled, each keel ending in a spine ; a circlet 

 of horizontal spines around the base of the caudal. The two elongate, 

 subrectangular shields at the base of the ventrals are in the line of the 

 second series of dorsal plates, the first series terminating above the 

 pectorals. Twenty-seven irregular ]ilates on the imder surface of the 

 body in front of the ventral ]dates, Lat(n'al line simple, along the cen- 

 ter of the lateral surfaces. 



Color olivaceous or yellowish, with six or seven darker bands of brown 

 on the dorsal surfaces. Under side uniform whitish. Fins blotched with 

 blackish. 



Three specimens of this si)ecies are known to me ; two of them Avere 

 obtained in the markets of San Francisco. One of tln^se, which may be 

 considered as the type of the species, has been forwarded to the United 

 States National Museum, and is numbered 23504 on the Museum llegis- 

 ter. The third specimen was procured on the coast of Alaska by the 

 United States Coast Survey. The aspect of this fish is that of Acjonus, 

 but the presence of teeth on the vomer and palatines excludes it from 

 that genus. 



