216 ON THE NAIADES, 



valvuld utraque duplicibns ; lateralibus longis curvisque ; margaritd purpurea, 

 aut salmonis colore tinctd. 



Shell trapezoidal, transverse, inequilateral, inflated ; valves rather thick ; beaks 

 slightly elevated and transversely wrinkled ; cardinal teeth compressed and double in 

 both valves ; lateral teeth long and curved ; nacre purple or salmon. 



Hab. Santee Canal, South Carolina. Professor Ravenel. 



My Cabinet. 



Cabinet of Professor Ravenel. 



Diam. 1-1, Length 1-3, Breadth 2-4 inches. 



Shell trapezoidal, transverse, inequilateral, inflated ; substance of the 

 shell rather thick ; beaks slightly elevated, incurved, transversely wrin- 

 kled ; umbones very much swollen ; ligament rather short and thin ; 

 epidermis dark brown, shining; cardinal teeth very much compressed; 

 lateral teeth long and slightly curved ; anterior cicatrices distinct ; pos- 

 terior cicatrices confluent ; dorsal cicatrices on the superior part of the 

 cavity of the beaks ; cavity of the shell very deep ; cavity of the beaks 

 full and rounded ; nacre purple or salmon. 



Remarks. — The confer lus, in its general characters, resembles the 

 complanatus (Solander). It is, however, much more inflated, and dif- 

 fers in having teeth more compressed. The specimens in my cabinet 

 I owe to the kindness of professor Ravenel. These are all without 

 rays. In young specimens they may exist. 



Symphynota Benedictensis. Plate XVI. fig:. 48 



»• 



Testa trapezia simill, inxquihterd, transversa, subcompressd, margine dorsali 

 subrecta ; valvulis perlenuibus; natibus subprominentibus, apicibus grunulatis ; 

 cicatricibus vix cernendis ; margaritd ccBruleo-albd et iridescente. 



Shell trapezoidal, inequilateral, transverse, rather compressed, nearly straight on the 

 dorsal margin; valves very thin ; beaks somewhat prominent, and granulate at tip ; 

 cicatrices scarcely perceptible ; nacre bluish white and iridescent. 



Hab. Lake Champlain. 



