81 



upper jaw is one third the length of the fish ; it is separated from 

 the second dorsal by a space about equal to the height of the fiith 

 ray ; the spines are all slender ; the height of the third spinal ray, 

 which is the highest, the first being very short, is equal to the length 

 of the fin, or a little less than half the length of the head. 



The length of the second dorsal is about one-sixth of the length 

 of the fish ; its greatest height, which is at the second soft ray, is 

 equal to that of the first dorsal, and three times its height posteri- 

 orly ; its first two rays are spinous, short. 



The anal fin cquaUing the second dorsal in height, and similar to 

 it in form, but longer, has its first four rays spinous ; its origin is a 

 little anterior to the line of the jniddle of the second dorsal. 



The pectorals are pointed, having a height equal to half the 

 length of the head, their length being one-thu'd their height. 



The ventrals, situated a little posterior to the pectorals, do not 

 quite equal them in height. 



The caudal is slightly concave, the height of its external rays 

 being about equal to the length of the second dorsal. 



D. VIII, IL 19, A. IV. 20, P. 18, V. I. 6, C. 6, 1. 8, 8, 1, 6. 



Color grayish brown above, silvery on the sides and beneath. 



This species is by no means common, only two or three speci- 

 mens having yet been observed, none of which exceeded eight 

 inches in length. They were all obtained in the markets of San 

 Francisco having undoubtedly been caught in the bay. 



It is with much reluctance that I propose a new generic division 

 in this family. The allied genera seem to me not well studied, and 

 to need a careful revision. The arrangement of the teeth, however, 

 in the present species, is such as to separate it from any genus now 

 recognized. It may be thus characterized 



Seriphus (Ayres). — Dorsal fins, two, distinct; branchial aper- 

 tures contiiiuous ; branchial rays, six; no cirrhi; teeth iyi both 

 jaivs, sharp, distinct, nearly even in size, in a. double or sinyle row, 

 none on the vomer or palatines : anal spines feeble. 



The genus is very closely allied to Jolmius. 



^ December ^,18G0. 

 President in the Chair. 



Dr. Ayres read the following descriptions : 



'' amarina nigricans, (Ayres) Fig. 22. — Form oval, elon- 

 gated, compact, compressed ; snout blunt ; dorsal and ventral out- 

 lines nearly evenly arched ; greatest depth a little more than one- 

 ihird of the total length ; length of the iicad constituting not quite 



