26 BuivLETIN 4 140 



(often indurated) marl is most conspicuous. Immediately at the 

 landing no well preserved fossils were found, but the outcrops per- 

 haps 100 yards below furnished Cucullcea inacrodonta, Protocardia 

 nicolletti \2iX . (large and perfectly preserved), Astarte sniithvillensis 

 var. , Veriericardia alticostata var. , Peden alabaviensis , Meretrix, 

 Ostrea, Dentaliuni, Pseiidoliva unicarinata, Volutilithes var. saffordi, 

 Fiisus vio/iri, Natica eminula^ N. alabauiiensis, Valuta showalteri, 

 Cylich?ia (pi. 7, fig. 7). 



Prairie Bluff and vicinity. — Prairie Bluff on the Alabama has 

 long been known as a typical upper Cretaceous collecting ground; 

 and strange to relate, from the time of Winchell's visit in the 

 fifties until ours of last summer the Eocene character of the sur- 

 face rocks on this bluff and its immediate vicinity had never been 

 detected. Smith and Johnson's general section of this locality as 

 published in 1887, in Bull. 43, U. S. Geol. Surv. and 1895 in the 

 State Survey report of that year is reproduced in this treatise 

 along with the Oak Hill-Pine Barren section. Our interpretation 

 of the same is therewith given. 



Since this is one of the localities in this part of the State most 

 frequented by collectors, we feel it not out of place to give a con- 

 siderable number of details in its description. 



Our general section taken from outcrops at the Bluff and many 

 others from ^ to 2 miles to the north is given below: 



Tops of highest hills to the north of Prairie Bluff. 

 Sandy layers with some clayey limestone. One 

 Enclimatoceras observed. 



a. Bluish clay with ledges of impure light or slightly 



yellowish limestone; fossils scarce, - 15 feet. 



b. Very much as in "<2" but characterized by a 



JLucina, . . . . . ^o feet. 



c. Yellowish gray limestone with Enclimatoceras, i foot. 



d. Bluish clay with bands of impure limestone con- 



taining Enclhnatoceras , . . - 20 feet. 



e. Clayey and limy layer with Enclimatoceras, Veneri- 



cardia, Cuczillcsa, etc., . . . 2-3 feet. 



/. A continuation of bed "<?" but becoming more 

 clayey, calcareous and bluish above; below hav- 

 ing the texture of brown sugar, or sandy and 

 unfossiliferous, and finally pebbly with rolled 

 Belemnites and Exogyra fragments, - 8-12 feet. 



g. Blue clay with Cretaceous fossils. 



The contact of the Midway and Cretaceous beds can be seen at 

 the Bluff in the little channels that cut the surface rocks just 

 south of the cotton storage shed. But the best and most fossilif- 

 erous exposures are to be found a mile or two from the landing. 



