12 PROCEEDINGS OF THE ACADEMY OF [Jan., 



Peoten perlamellosus Whitfield, Mon. u. S. Geol. Sur., IX, 50, pi. VII. f. 7, 1885. 

 Peoten conradi Whitfield, Mon. U. S. Geol. Sur., IX, 52, pi. VII, figs. 8-10, 1885. 



This is the P. simplicus Conrad in part. 

 Neithea complexicosta Gnbb, Proc. Acad. Nat. Sci., 1876, 319. 



Probably only a form of N. quinquecostata Sowb. 



SPONDYLID^. 



Spondylus gregale (Morton). 



Plagiostoma gregale Mort., Syn. Org. Rem., 60, pi. V, f. 6, 1834. 



Dianohora eoMnata (Morton). 



Plagiostoma echinatum Mort., Syn. Org. Rem., Add. Obs., IV, 1835. 

 Spondylus capax Conr., Jour. Acad. Nat. Sci., II, 2 ser., 274, pi. 24, f. 8. 

 Dianchora echinata Wliitf., Mon. U. S. Geol. Sur., IX, 59, pi. X, figs. 3-5. 



Morton's and Conrad's species are based on the same shell, a very 



convex free valve. 



Plioatula urticosa Morton, Syn. Org. Rem., 62, pi. X, f. 2, 1831. 



Plioatula tetrica Conrad. Jour. Acad. Nat. Sci., IV, 2 ser., 283, pi. 46, f. 26, 1860. 



1.1MIDJE. 

 Lima pelagica (Morton). 



Plagiostoma pelagicum Mort., Syn. Org. Rem., 61, pi. V, f. 2, 1834. 

 Lima squarrosa (Gabb). 



Ctenoides squarrosa Gabb, Proc. Acad. Nat. Sci., 1861, 366. 

 Lima acutilineata (Conrad). 



Specimens figured by Whitfield {Mon. U. S. Geol. Sur., IX, 62, pi. 9, 

 figs. 6, 7). 



ANOMIID^E. 

 Anomia argentaria Morton, Amer. Jour. Sci., XXIII, 293, pi. 5, f. 10, 1833. 

 Anomia argentaria Morton, var. ornata Gabb. 



Anomia tellinoides Morton, Amer. Jour. Sci., XXIII, 294, p. 5, f. 11, 1833. 

 Paranomia scabra (Morton). 



Placuna scabra Mort., Syn. Org. Rem., 62, 1834. 



Figured by Whitfield (Mo^i. U. S. Geol. Sur., IX, 44, pi. X, fig. 10). 



Paranomia lineata (fourad). 



Placunanomia lineata Conr., Jour. Acad. Nat. Sci., IV, 2 ser., 291, pi. 46, 

 f. 20. 



Paranomia salFordi Conrad, Am. Jour. Conch., Ill, 8. 



Liroscapha squamosa Conrad, Am. Jour. Conch., V, 100, pi. 9, f. 23, 1869. 



MYTILID^, 

 Modiolus Julia Lea, Proc. Acad. Nat. Sci., 1861, 149. 



Specimen figured by Wliitfield (pi. 17, f. 6). Probably the type. 



Modiolus burlingtonensis Whitfield, Mon. U. S. Geol. Sur., IX, 66, pi. 17, figs. 8, 9, 1885. 

 Modiolus ovatus Gabb, Jour. Acad. Nat. Sci., IV, 2 ser., 396, pi. 68, f. 31, 18G0. 



