1818.] OF THE UNITED STATES. 395 



and rarely in that of the Rock {Perca SexatUisf^ Bloch). 

 I have not access to any descriptions of C. Gauddoupen- 

 sis and Americana thct can be considered as specific, so 

 that it is possible I have here named them erroneously, if 

 tills should prove to be the case, I will gladly embrace 

 the first opportunity to reject the false name and restore 

 the true one, that first given. 



Nicholson in his Essai sur PHist. Nat. de St. Do- 

 mingo, p. 343, pi. 7, fig. 2, gives an account and figures 

 of a species of Cymothoa much resembling this, under 

 the name of Pou de Sarde^ Pediculus mannus. He found 

 it in the branchia of a " Sarde." 



2. C. pragustator. Body elongated; eyes conspicu- 

 ous; head not attenuated, much longer than broad; tail^ 

 terminal segment as long as the seven preceding ones 

 conjunctly. 



Inhabits mouth of Clupea TyrannusX of Mr. Latrobe. 

 Oniscus pragustator. Mr. B. H. Latrobe, Trans. Amen 

 Philos. Soc. vol. V. p. 77, plate 1. 



Cabinet of the Academy. 



Body elongated, gradually attenuated before, from the 

 sixth segment; head narrower than the first segment, 

 elongated, transversely impressed near the tip, tip not 

 narrowed; eyes conspicuous, oval, composed of punc- 

 tures instead of granules; antenna subequal, hardly at- 

 taining the middle of the eyes; firsts second, third, and 

 fourth segments nearly equal in length, the first rather 

 longer, fifth, sixth and seventh shorter, the latter very 

 much lunated to receive the abdomen; abdomen and tail 



f Described subsequently by Dr. Mitchill under the name of P. Mitchilli, 

 % Described subsequently by Dr. MitckiU under the name of C menhaderu 



n.:-^v 



