28 



Bulletin 4 



143 



Venericardia , Osti'-ea p7i!aske7is7s oxidi O. cren^dimarginata. 



In the hill just north of the Bluff numerous specimens of a 

 Liichia were obtained. Thej^ are usually coated over with a cal- 

 careous clayey substance, and oftentimes more or less distorted. 

 Owing to their imperfect state of preservation it is impossible to 

 say for certain whether they belong to species already described 

 or not. Similar specimens have been seen on the Brazos river as 

 w^ell as on the Tombigbee. Accompanying this species are 

 Enclimatoceras idrichi, T^writella mortojii var. and Yoldia eborea. 



The Cretaceous-Eocene contact is well exhibited along Shell 

 creek about i Y^ miles southwest of Prairie Bluff. Fig. 3 shows 

 in a general way the irregularity of the upper surface of the light 

 blue Cretaceous sandy clay, and also the coarse pebbly character 

 of the lower layers of the superincumbent arenaceous bed. A 

 section from the bed of this stream to the level of the high land 

 to the south is as follows: — 



a. Limestone layers, . . - - 10? feet. 



b. Bluish sandy and micaceous clays interspersed 



with calcareous ledges (beds a, b, c 8i.d oi the 







Fig. 3. — Cretackous-Eocene Contact, 

 ON Shell Creek, Ala. 



