76 Bulletin 15 386 



Sefiio?i at Grand Gulf {see page 75). A se(5lion at Grand 

 Gulf, about half a mile above the town, was made by Prof. Harris 

 in 1902. The most striking feature is the occurrence of a bed of 

 pebbles above the coarse white sandstone. These mark the upper 

 limit of the Grand Gulf series. The sandstone which occurs 

 above the pebbles is a variable bed, poorly consolidated, and 

 passes into sandy clays and loess. The alternation of sandy and 

 clayey beds in the bluff is well marked by the effecfts of erosion. 



Towards the southeastern part of the state the sandstones 

 lose the typically arenaceous character which they exhibit at 

 Grand Gulf, and merge into variously colored clays, often con- 

 taining potash and soda. The clays are similar to those in 

 Alabama. 



Flora and fauna of Graiid Gulf beds. The Grand Gulf beds 

 in Mississippi contain abundant remains of dicotyledenous and 

 coniferous trees and palms. The flora is richest in the upper beds 

 of the series, at Hattiesburg, where the plant remains 

 correspond to those of the Alum Bluff sands. Few animal 

 remains have thus far been noted. A cast of Uyiio was found by 

 Mr. Johnson, casts of freshwater bivalves by Mr. Meyer* and 

 fragments of turtle by Dr. Hilgard.f The formation is thus 

 shown to pass into freshwater beds to the westward of Alabama. 



Louisiana. 



The Vicksburg limestone. The yicksburg limestone^ appears 

 in Louisiana only in the vicinity of Rosefield, and probably along 

 Bayou Funne Louis. Mr. Vaughan|| has obtained typical Vicks- 



* Amer. Jour. Sci., 3rd ser., vol. 32, 1886, p. 25. 



-\ Ibid., vol. 22, p. 59. 



X Dr. Hilgard assigned a far larger area to this formation in IvOuisiana 

 than recent investigation has shown it to occupy. (See Harris and Veatch, 

 Geol. Survey La., 1899, pp. 93-4). In 1869 {Amer. Jour. Sd., 2nd ser., vol. 

 47, pp. 78-88), he refers nearly all the marine Tertiary of the state to the 

 Vicksburg. See also the Supplementary and Final Report oj a Geol. Recon- 

 naissance in La., 1883. 



\Amer. Geol., vol. 15, 1895, pp. 205-229. 



