Granitnichthys Kaup. 

 Trinectus Raf. 



NATURAL SCIENCES OF PHILADELPHIA. 215 



Family SOLEOIDJE, Bon. 



Subfamily SOLEIN2E, (Bon.) 



ACHIRUS, Lac. 



ACHIRUS LINEATUS, CUV. 



Pleuronectus achirus L. 

 Pleuronectus lineatus L. 

 Achirus fasoiatus Lac. 

 Pleuronectes mollis Mit. 

 Achirus (lineatus) Cuv. 

 Achirus mollis St. 

 Gramniichthys lineatus Kaup. 

 Solea achirus Gthr. 



Subfamily PLAGUSINJE. 



PLAGUSIA, Brown. 

 Aphoristia Kaup. 

 Glossichthys Gill. 



Plagusia plagiusa, Gill. 



Pleuronectes plagiusa Linn. 

 Plagusia fasciata Dele. 

 Glossichthys plagiusa Gill. 

 Hab. North and South Carolina. 



Family PLEURONECTOIDJE, Bon. 



We owe to Cuvier the first natural subdivision of the genus Pleuronectes, 

 as restricted by Quensel. That great philosopher distributed the representa- 

 tives of the genus thus limited, which is equivalent to a family in the modern 

 acceptation of the word, among three subgenera : Platessa, in which the 

 teeth of the jaws are uniserial, trenchant and obtuse, and those of the 

 pharyngeal" bones blunt ; Hippoglossus, in which all the teeth are strong 

 and acute, and Rhombus, similar to the latter, but with the dorsal advanced 

 towards the edge of the upper jaw. The species respectively referred to 

 these several groups are evidently closely related, and all possess characters 

 coincident with those assigned by Cuvier, and apparently of greater value. 



The Platessce have a small oblique mouth in front of the eyes ; the Hippo- 

 fjlossi, a large one extending below the eye ; and in the Rhombi, the ventral 

 fins are very broad at their bases, the rays distant, and the fin of the colored 

 side on the ridge of the abdomen. These groups correspond to the subfamilies 

 Pleuronectina?, Hippoglossinae and Rhombinfe as now limited, and thus have 

 different elements from the subfamilies of Bonaparte. The natural character 

 of these groups was first destroyed by the reference to the Platessae of the 

 Plmrcweetes limandoides of Bloch. This fish was referred by Cuvier to the 

 genus Hippoglossus, but was subsequently transferred by all naturalists to the 

 genus Platessa, with which it neither agrees in technical characters nor in 

 natural ones. Subsequent modifications of the subgenera of Cuvier rendered 

 them still less natural, and the American species, especially, were grouped 

 little in accordance with their affinities. In the following synopsis of the Pit -- 

 ronectoids of Eastern North America, I have distributed the species in accord- 

 ance with the Cuvierian ideas. 



I. Mouth small, the supramaxillary ending before or un- 

 der front of eye PleueonectinjE. 



A. Body with scattered ciliated scales. Teeth move- 

 able Euchalarodus. 



1864.] 



