VAUGHAN AND COOKE: HAWTHORN FORMATION 251 



feel 



1. Gray soil, sand, and humus 2 



2. White sand 4 



3. Clay with silicified corals and oyster (Hawthorne beds) 6-8 



4. Indurated clayey rock (Hawthorne beds?) 2 



o. Clayey sand-rock, rather fine-grained and soft 4 



6. The same, somewhat coarser and harder 8-10 



7. Sand rock of coarser, sharp grains, coated and cemented together 



with white, limy matter 4-6 



8. Foraminiferal Eocene top-rock (Vicksburg) indefinitely below 



The silicified corals of bed No. 3 are sometimes 20 to 60 pounds in 

 weight, and along the river when dislodged from the clay often wear 

 immense potholes in the softer lime rocks. Miocene sharks' teeth 

 and fragments of bone also occur in the clay. Under bed No. 8, when 

 it is tilted up, as occurs in various places along the river, is found the 

 older Orbitoides limestone of the Vicksburg group. 



The following is a description of a section observed by us near 

 ^\'^lite Springs: 



Section, Rock Island and spring about 250 feet above it, left bank of Suivan- 

 nee River, about three-quarters of a mile in a straight line above the White 

 Springs wagori bridge. 



THICKNESS 



feet inches 



10. Terrace material about 60 feet above water level in the 

 river. This represents the extensive, highest terrace 

 recognized along Suwanne River, — the sands grayish or 



white 12 



9. Yellowish sands, about 12 



8. Grayish sand on surface, float of oyster shells, etc., about. . 13 

 7. Bed with gra}' concretions, immediately above which are 

 many silicified Ostrea mauricensis, Siderastrea sp., and 



fossil bones, probably manatee 1 



6. Greenish sands and clays 1 



0. Calcareous quartz sands coated by calcium carbonate; nu- 

 merous phosphatic particles. Fossils: Orbitolites, Ostrea, 



etc 4 



4. Calcareous sands containing rotten shell fragments 1 2 



3. Light colored, greenish-gray sandy marl containing many 

 fossil shells but fewer specimens of Pecten than the under- 

 lying bed 4 9 



2. Base of spring section, light colored, greenish-gray sandy 

 marl; sand grains clear quartz, mostly rounded. Many 

 blackish phosphatic particles. Fossils numerous: Gonio- 

 pora sp., Pecten madisonius var. sayanus, Ostrea mauri- 

 censis. (The dip of this bed is about 2| feet in 50 feet; 

 direction S. 50° E., that is up stream. Between it and 

 the chert and limestone exposed at Rock Island it is 

 estimated that about 5 feet are concealed.) 2 6 



