16 



PROCEEDINGS OF THE ACADEMY OP 



This genus is represented by a single species, and is distinguished from i? 

 opropoma chiefly by the modification of the dorsal fin, but differs also by other 

 less important peculiarities. The name of Chorististium has been bestowed on it 

 in allusion to the separation of the second dorsal from the first,* on account of 

 the atrophy of the antecedent spines of the former which occur in Liopropoma. 



Genus Siniperca Gill. 



Perca Basileivski, Noveaux Memoires de la Societe Imperiale des Naturalistes de 

 Moscou. Tome x., p. 217. 1855. 

 Non Perca, Linn. 



Body oblong and compressed, covered with small scales. Lateral line little 

 arched in front. Head mostly scaleless, oblong, with the profile slightly in- 

 curved to the eyes, and with the snout conic and slightly convex before eyes. 

 Eyes small, entirely in the anterior half of the head. Mouth rather large, the 

 supramaxillary bones continued under or behind the eyes. Lower jaw promi- 

 nent. Teeth villiform on the jaws, vomer and palatine bones. Preoperculum 

 serrated behind, beneath with three or four spines or lobes. Operculum termi- 

 nating in a spine. Branchiostegal rays seven. .Dorsal fins connected at base; 

 the first arched, with twelve spines ; the second short and quadrate. Anal with 

 three spines, the second of which is short or moderate; the soft part corre- 

 sponding to the second dorsal. Caudal entire. Pectoral fins rounded behind. 



Type. Siniperca chua-tsi, Gill. 



Syn. Perca chua-tsi, Basilewski, op, cit., tome x., p. 218, tab. 1, fig. 1. 



This is a very distinct and peculiar genus, its physiognomy recalling to mind 

 the Lates calcarifer more than any other fish, but it widely differs from Lates in 

 the development of the first dorsal fin, the almost or quite naked head, the 

 small size of the scales on the trunk and the slight armature of the opercular 

 bones. It is composed of only two known species, the Perca chua-tsi and P. 

 chuan-tsi of Basilewski, both of which are inhabitants of the Chinese rivers. 

 In allusion to this restriction of habitat to the Chinese Empire, the name of 

 Siniperca may be given. Dr. Basilewski has very well formulated the charac- 

 ters of the genus, but he has unfortuuately employed for it the name of Perca ; 

 the latter must of course be retained for that to which it was originally given, 

 and it then becomes necessary to rename the Chinese fishes. 



Note on the SCIJENOIDS of California. 



BY THEODORE GILL. 



Dr. Ayres has recently described, in the "Proceedings of the California 

 Academy of Natural Sciences," two new species of Sciaenoids, for one of which 

 he has framed a new genus, (Seriphus,) and the other has been referred to 

 Johnius. Dr. Ayres has also expressed his belief in the close affinity of Se- 

 riphus and Johnius. On perusing his description, and after an examination of 

 his outline figures, I am convinced that Seriphus is most closely allied to that 

 as yet unnamed genus of which the Ancylodon parvipinnis of Cuvier and Va- 

 lenciennes is the type, while the Johnius nobilis belongs to one nearly allied to 

 the weak fishes ( Cynoscion) of the Eastern American coast, and is congeneric 

 with Cuvier 's Otolithus cequidens of the Cape of Good Hope. The two species 

 of California are consequently not only generically distinct, but they appear 

 to me to represent two subfamilies, equally distinct from each other and from 

 the Scireninfe.f 



* X&>p/trToc, separate and 'Is-tiov, sail. 



*It may be here remarked that the genus Camarina of Ayres is not at all related to 

 the Pomacentroids, but is synonymous with the genus Girella of Gray and Gu'nther. 

 Dr. Ayres has stated that the " genus,-though resembling in general features some species 

 of Pomacentrus, presents a new grouping of generic characters." 



[Jan. 



