MOLLUSCA. 79 



of Natural History at Paris. But the truth is, that it was 

 found by M. Cortezi, Counsellor at Parma, and a success- 

 ful investigator of the organic remains of that district. It 

 ought, therefore, to have obtained the name of P., Cortezi, 

 in honour of the discoverer, instead of the name of Faujas 

 St. Fond, who received it from M. Cortezi, and whose sole 

 merit in the subject consisted in his bringing it in safety 

 to Paris. 



The principal error of Linnaeus in the construction of this 

 genus, consisted in the insertion of fluviatile shells among 

 his marine species. Bruguiere readily perceived this error, 

 and formed a new genus for their reception, which he called 

 UNIO. But this group, now denominated NAYADES by La- 

 mark, includes the genera unio hyria, anadonta tridina, and, 

 we may add, alasmodon. 



5. SOLEN. This genus has undergone few changes since 

 the days of Linnaeus. . The character has been somewhat 

 restricted, and those species have been removed, in which 

 the external margin is a little arcuated, and the cardinal 

 teeth articulated, and two in number, and formed by Lamark 

 into a new genus, which he terrns SANGUINOL.ARIA. The 

 animals of this genus, according to Poli, differ from the so- 

 lens, in having the tubes of the syphon separate, and of 

 unequal length and thickness. The 8. minutus of Linnaeus, 

 found in our seas, is referred to the genus HIATEKLA by 

 Cuvier, a genus very imperfectly defined, but nearly allied 

 to, if it be not identical with, the byssomia of the same au- 

 thor, which includes the mytilus rugosus of Linnaeus. 



6. TELJLINA. This extensive genus of Linnaeus, the es- 

 sential character of which is to have an anterior inflection 

 or fold in each valve, and lateral teeth, includes many shells 

 which differ greatly in form and habit, and which disagree 



