Vol. XVI, pp. 5-8 February 21, 1903 



PROCEEDINGS 



or THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



REVIEW OF THE CLASSIFICATION OF THE 

 CYRENACEA. 



BY WILLIAM H. DALL. 



In working over the Cyrenacea for the Memoir on the Ter- 

 tiary Fossils of Florida, in course of publication by the Wagner 

 Institute of Science, it was found that both the nomenclature 

 and the classification were in a state of deplorable confusion. 

 While the details are reserved for that memoir, it was thought 

 that a synopsis of the arrangement adopted might be of use to 

 the students of the group, and it is hei-ewith presented. 



Family Cyrenidoe. 



Genus Miodontoptis Dall (nov.). Type Cyrena media Sowerby. Juras- 

 sic. This is Miodon Sandberger, 1870, not Carpenter, 1865. 



Genus Loxoptychodon Sandberger, 1872. Type Cyrena intermedia De- 

 shayes. Lower Eocene, France. 



Genus Plesiastarte Fisher, 1887. Type P. crenulata Deshayes (as 

 Cyrena). Lower Eocene, France. 



This is Anomala Cossmann, 1886, not Hiibner, 1816. 



Genus Ditypodon Sandberger, 1872. Type Cyrena suessii C. Mayer. 

 Lower Pliocene of Italy. 



?Genus Donacopsis Sandberger, 1872. Type Cyrena acutangularis De- 

 3— Phoc. Biol. Soc. Wash. vol. XVI, iy03. (6) 



