1881.] NATURAL SCIENCES OF PHILADELPHIA. 449 



I have seen no specimen of this species, and therefore rely 

 solely upon the description and figure as given by Rogers ; I am 

 inclined to doubt its validity. 



A. rhomboidella Lea. (Anomalocardia). Ala' 



"Contributions to Geology," p. 74. 



A. Bogersi Heilpr. V;i . 



Area (Cucullcea) transversa Rogers. Trans. Am. Phil. Soc, 1839, 

 p. 373. Specific name transversa, preoccupied by Say. 



I have seen no specimen of this species, and judging from the 

 figures illustrative of Rogers' description it appears as though it 

 may prove to be only a variety of A. onochela. 



Oligocene. 

 A. lima Conr. Miss. 



J. A. N. S., i, 2d ser., p. 125, as Byssoarea. 



A. {Byssoarea) Mississippiensis Conr. (young). J. A. N. S., i, 2d ser., 



p. 125. 



This species is most closely related to the A. rudis Desh., an 

 Eocene, Oligocene and Miocene (?) fossil of western and southern 

 Europe ; it differs from the recent A. Helhingii Brug. (= A. 

 harhata L. ?), of which the A. rudis is stated by Deshayes to be 

 possibly only a variety, in the strong carination of the posterior 

 slope. 



A. Mississippiensis Conr. Miss. 



J. A. N. S., i, 2d ser., p. 125. 



A. sabprotracta Heilpr. Mis?. 



Conrad, J. A. N. S., i, 2d ser., p. 126, as Byssoarea protracta ; specific 

 name preoccupied by Rogers, Trans. Am. Phil. Soc, new ser., v, 

 p. 332. 



Miocene. 



A. arata Say (Scapharca). Md. 



J. A. N. 8., iv, p. 137. Conr., Mioc. Foss., p. 58. 



This species is enumerated on the authority of Sa}^ and Conrad ; 

 I have seen no specimens of it, and am doubtful whether it is not 

 a form subsequently described under a new name by Conrad. It 

 seems to have been closely related either to A. limula or A. Car- 

 olinensis. 



A. brevidesma Conr. N. Car. 



Mioc. Foss., p. 62, 



(Not enumerated in the " Smithsonian Check List " of 1864.) 



