60 



Aug-ust 6, 1860. 

 President in the Chair. 



Dr. Ayres presented the following descriptions of new fishes : 



Trichodon lineatus (Ayres). Fig. 11. Form elongated, much 

 compressed, broadest just behind the eyes, tapering in thickness 

 thence gradually to the caudal fin ; top of the head flattened ; dor- 

 sal outline very slightly arched ; abdominal outline strongly curved ; 

 greatest depth about equal to the length of the head, or one-fourth 

 of the length of the fish ; depth of the peduncle of the tail one- 

 fourth of the greatest depth. 



Mouth almost vertical ; the tip of the lower jaw, when closed, 

 rising above the level of the top of the head. The extent of the 

 upper jaw to the tip of the maxillary, is more than half the great- 

 est depth of the head ; teeth numerous, slender, curved, sharp- 

 pointed in both jaws and on the vomer ; none on the palatines ; the 

 largest are on the front and sides of the lower jaw. 



Operculum smooth. Preoperculum with five or six long rowel- 

 like teeth (only four are shown on the plate) radiating from near 

 its angle ; anterior suborbital bone with two strong teeth directed 

 forward and downward. 



Eye near the top of the head, large ; its diameter being a little 

 less than one-third the length of the head. 



Branchial apertures large, continuous beneath ; branchial rays, 

 four. 



The distance of the origin of the first dorsal fin from the tip of 

 the upper jaw, is about one-third the length of the fish excluding 

 the caudal fin ; its outline is arched above, diminishing from the 

 fifth and sixth spines in both directions, but most gradually poste- 

 riorly ; its length, which is three times its height, is a little less 

 than one fourth the length of the fish ; the spines are all slender. 



The second dorsal is separated by a short interval from the first, 

 which it slightly exceeds in both length and height ; the rays are 

 all articulated but scarcely branched. 



The anal, coterminal with the second dorsal, is one-third as long 

 as the entire fish ; the first two-fifths of the fin are low, of nearly 

 uniform height ; the height is then suddenly about doubled, and 

 from that point diminishes gradually to its termination ; the rays 

 are like that of the second dorsal. 



The caudal is nearly even posteriorly ; the accessory rays very 

 numerous. 



D. XV. 18, A. 28, P. 23, V. 5, C. 14, 1, 5. 6, 1, 14. 



Color above greenish olive, with two or three somewhat irregular 

 rows of blackish blotches constituting interrupted longitudinal lines. 



