78 MOLLUSCA. 



shell presented some difficulty to Linnaeus, as he placed it 

 at first among the Pinna, and afterwards among the Myce. 

 Even Bruguiere gave it a place among the oysters. 



Another genus has been formed by Lamark from the mya 

 siliqua of Chemn. (Conch.vol.*i. p. 192, tab. 198, fig. 1934). 

 He calls it GLYCIMERIS. Though nearly related to the true 

 myae, by gaping at both extremities, yet it differs from them 

 in the hinge, which is destitute of teeth, and in the ligament 

 being external. 



A new genus was formed by M. M. Groye, (Annales du 

 Museum, vol. ix.), which he terms PANOPEA, and assigns 

 to it the following characters : " Coquille transverse, bail- 

 lante inegalement au deux bouts, charniere semblable dans 

 Tune et dans Tautre valve, ayant une callosite ou grosse dent 

 allongee, placee en avant et sur le corselet ; decurrente sur 

 le bord interieur, relevee en arete, mousse et saillarit poste- 

 rieurement ; une dent cardinale conique un peu comprimee 

 et arquee, et sur le valve droit une fosette dans laquelle s'en- 

 grene la dent de la valve opposee ; ligament exterieur, cro- 

 chets peu protuberans, corselet large, deux impressions 

 musculaires dans chaque valve situees vers les extremites." 

 The type of this genus is the mya glycimeris of Gmelin first 

 noticed by Aldrovandus. It is inserted among the British 

 shells by Mr. Donovan upon very slight authority. In the 

 construction of the genus, we think, that M. Groye has acted 

 properly, but there was no necessity surely for changing the 

 trivial name (of the first described species) bestowed upon 

 it by the discoverer. He has added another species from 

 Monte Pulgnasco in Parma. In the trivial name of this 

 species, we consider that he has been guilty of an act of 

 injustice. He has called it P. Faujas, in honour of Faujas 

 St. Fond, the zealous Professor of Geology in the Museum 



