The Tertiary Fauna of Nezvfon and Waiitiibhee, Miss. 45 



Indistinct revolving impressed lines are only visible under a 

 strong glass. The conical top is distinctly defined from the cylin- 

 drical body. 



Lamellibranchiata, 

 Plicatiila plaiiata, n. sp. 

 Plate II. Figure 20. 

 Covered by small, radiating ribs, consisting of scales and 

 scaly spines. They are larger in rather regular intervals, es- 

 pecially on the sides, and their spines are sometimes rather long. 

 The umbonial part, however, is smooth. 

 Newton, Wautubbee. 

 The type specimen is from Newton. 



Pcctot piilchricosfa, n. sp. 

 Plate II. Figure 23, 23^7. 

 Convex, covered by eight broad, rounded, radiating ribs, 

 perceptible in the inside ; those in the middle are the largest. 

 Near the ventral margin they dissolve into more numerous ribs. 

 Wautubbee. . - 



Only the figured valve is known. 



Witcyicardia coniphwicosta, n. sp. 

 Plate II. Figure 21, 2\a. 



Rather small. Cordate. Very much inflated. Beak large. 

 Covered by compound, elevated ribs, crenulated near the umbo. 

 They consist of a large median and two small side-ribs. Margin 

 crenulate within, in correspondence with the outer ribs. 



Wautubbee. 



Vcncricardia Moorcaiia Gal)b, from Texas, and T?//. pcranii- 

 qua Conr. (K subqiiadrafa Gabb), from New Jersey, have similar 

 ribs, but are less inflated ; have a rounded ventral margin and a 

 smaller beak. 



Corhula Miircliisoni Lea var. fossa fa n. var. 

 Plate II. Figure 22. 



Like Corhula Murchisoui Lea, from Claiborne, but the con- 

 centric ribs terminate rather abruptly at a depressed line along the 

 carina. Between this line and the carina there are double the 

 number of small concentric ribs. The form, besides, is smaller 

 than in Claiborne. 



Newton ; Wautubbee ; Lisbon, Ala. 



