NATUaAL SCIENCES OF PHILADELPHIA. 



213 



The following were presented for publication : 



" Descriptions of the G-obioid Genera of Western North America/' 

 ' Note on the Genera Hemirainphinai," and " On the Genus Perioph- 

 thalmus." By Theo. Gill. 



" Description of a collection of Jasper Lance-heads, found near 

 Trenton, N. J." By Charles C. Abbott. 



" Descriptions of new and little known species of Picidaj, etc." By 

 John Cassin. 



Sept. 2dlh. 

 Mr. Vaux, Vice-President, in the Chair. 



Eighteen members present. 



On report of the Committee, Mr. Cassin's paper, read Sept. 22d, 

 was ordered to be published in the Journal. 



On leave granted, Dr. Bridges presented a paper entitled " Supple- 

 ment to descriptions of soft parts and embryonic forms of Unionidaj." 

 By Isaae Lea. Which, on report of a Committee, was ordered to be 

 published in the Journal. 



On report of the respective committees, the following were ordered 

 to be published : 



Synopsis of the POMACENTEUIDS of the Western Coast of North and Cen- 

 tral America. 



BY THEODORE GILL. 



As some of the species of the family of Pomacentroids inhabiting the Pa- 

 cific waters of our continent have been involved in confusion, and very diverse 

 species united, the present article is submitted in rectification of such errors, 

 and of others formerly committed by the author. 



The family of Pomacentroids is accepted with the types referred to it by 

 Dr. Giinther ; that gentleman has, however, lately established a genus called 

 Melambaphes* for a species supposed to be the Giypliisodon nigroris of Cuvier 

 which he is uncertain whether to refer to the present family or the " group 

 Cantharina" of the Sparoids. His description does not enable us to positive- 

 ly decide, as he does not describe the course of the lateral line, which would 

 have probably enabled one to refer it to its proper family, the lateral line 

 being interrupted in the Pomacentroids, and continuous in the Sparoids and 

 l'imelepteroids. As the new genus is, however, characterized by its " small 

 ciliated scales " (L. lat. 100), the presence in each jaw of " a series of trench- 

 ant, tricuspid teeth, and with a broad band of villiform teeth behind," and of 

 " fourteen or thirteen spines in the dorsal fin, and three in the anal fin'' 

 there can be little doubt that it belongs to Gunther's " group Cantharina." 



The following artificial table will assist in the determination of the genera. 

 Lqridozygus, Parma and Acanthochromis are genera unknown to me through 

 autopsy: 



* Melambaptaes Gthr., An. and Mas;. Nat. Hist., ser.3, -vol. xi. p. 115. Dr. Gunther is perhaps mis- 

 taken in referring this species to the Glyphidodon nigroris, C. et V. ; those naturalists were too keen 

 and profound to have placed a species of MelambapAes in Glyphidodon afieran examination which 

 induced their surprise iu discovering three anal spines, notwithstanding the resemblance to the 

 Glyphidodon rahti and bengalensis. It is possible that the third spine was an ossified ray. The 

 Mdambaphes of Gunther having been then named from a misconception, it is better that it should 

 obtain a new name that shall not perpetuate the error : it may therefore be called M. Guentheri. 



1363.] 



