PHOLADOMYA. 



TESTA tenuis, subhyalina, transversa, ventri- 

 eosa, postice brevis, rotundata, antice pl{is 

 miniisve elongata, hians ; superne hiantula. 

 Cardo, foveola elongato-subtrigona et lamina 

 marginali in utraque valva. Ligamentum ex- 

 ternum, breviuseulum, externae laminarum car- 

 dinis parte affixum. Impressiones musculares 

 duae, indistineti. Sinus impressionis museuli 

 adhaerentis pallii, magnus. Umbones ap- 

 proximati. 



We rejoice in the opportunity of introducing this entirely 

 new Genus to the notice of our readers, which the kind- 

 ness of Mrs. Mawe has allowed us, particularly as the 

 discovery of a single recent species has led to the more 

 perfect knowledge of several fossils, whose Genus was 

 before exceedingly doubtful, insomuch that from a con- 

 sideration of their external appearance alone, authors 

 have been induced to place them in several genera, to 

 none of which they really belong. The only specimen 

 that we have ever seen was brought from the Island of 

 Tortola, by Mr. Nicholson, it was picked up on the coast, 

 and from its extreme tenuity, as well as its resemblance 

 to the Pholades, we are tempted to believe that it may 

 be one of that class of shells that protect themselves 

 from the fury of the ocean in cavities perforated in stone ; 

 or at least that it must live buried in the sand : for there 

 is no other evidence, even among the numerous fossil 

 species, of its being a piercing animal. 



The following generic character being drawn up, 

 principally from the recent specimen, several particulars 



