160 BALL AND STANLEY-BROWN APALACHICOLA RIVER GEOLOGY. 



The marl is extremely rich in fossils ; Mr Burns obtained over 400 

 species in a few days' work at this locality. It contains a certain pro- 

 portion of clay and much calcareous matter, and is of a pale yellowish 

 color. It shows no Orbitolites, but Orthaulax, Cyprasa, Ancilla, Fitsus, 

 Conus, Oerithium, etc, show characteristic fossils beautifully preserved 

 and of good size. It is probable that the beds which lie above the 

 Chipola have been denuded in this vicinity. The importance of the 

 section lies in the presence of the typical Chipola marl conformably 

 upon the Chattahoochee limestones, which last at Alum bluff are below 

 the surface of the river, if present. The left bank here seems to be 

 alluvial. 



Abes Spring and Section. — Three or four miles south from Baileys ferry, 

 on the left bank, is a settlement of scattered houses which from a spring 

 which issues near the river has received the name of Abes spring. It is 

 situated on the south line of township 1 south, range 9 west, section 17. 

 The right bank of the stream here seems to be low and alluvial, rather 

 densely wooded. 



The section here was measured with a steel tapeline on the left bank 

 of the Chipola river, Calhoun county, Florida, at the bluff about 200 

 feet north of the spring, which here flows from a wooden pipe. 



Section at Abes Spring. 



1. Superficial sands, about 4 feet. 



2. Reddish and yellowish streaked sands 30-32 '' 



3. Gray aluminous clay 19 " 



4. Chesapeake gray marl to water (variable) 7 " 



Total thickness above water 62 '' 



In detail these strata have the following composition : 



Number 1. — Pale yellowish gray incoherent sand, such as might be 

 deposited by a river during seasons of high water — less like beach-sand 

 than the analogous material at Alum bluff. 



Number 2. — Of the same character as number 3 of Alum bluff. The 

 material is generally a little coarser and the gravels a little larger, and 

 there is also greater heterogeneity in structure. 



Number 3.— Same as number 4 (aluminous clay) of Alum bluff. 



Number 4. — Chesapeake, just as at Alum bluff. 



Darlings Slide and Section. — On the Chipola river, a mile or more north 

 of Abes spring, is a " slide " where timber is cast into the river for the 

 construction of rafts, which are floated down the river to the mills at 

 Apalachicola, on the Gulf. This place is locally known as Darlings slide, 

 and is a very steep natural bank, affording an excellent section, though 



