The Sfrdfiijraiihji of X. W. Louisunid . — VdiKjhfm. 217 
Ouachita parish. The formation probabl}^ occupies high 
points till farther north on Bayou Saline."' 
Dr. Lerch, on p. 89 of his second report, gives a section in 
White Oak Creek ten miles northwest of Winnfield, which he 
considers to be the contact between the Jackson and his Upper 
Lignitic. He states: *"A similar section is seen in No. 7 (fig.) 
of foregoing pages. The characteristic bald prairies are 
abundant in the neighborhood, and in the dumps of wells with 
undrinkable water large selenite crystals and Jackson fossils 
have been collected." 
Both of these gentlemen have erred as to the age of 
these beds, as the following list of some of the more char- 
acteristic fossils from one of these prairies ten miles north- 
west of Winnfield will show. This collection was made by the 
Louisiana Geological Survey and was submitted to the author 
for study. My thanks are due to Prof. G. D. Harris for as- 
sistance in determining some of the mollusks. 
Fusus mortoniopsis Gabb. alabamieiisis Lea. 
Pseiuloliva vt'tusta Cox. I'l'cirn claibonit'iisis Cox. 
Cassidaria plaiiotccta .Mkv. and Lim(>i)sis aviciiloiilcs Con. 
Ald. Crassatclla toxalta Hahhis. 
Ilimella ti'xaiia H.\kris. ('orbula oiiiscus Con. 
Tiirrilella apita De Greg. Protocai-dia .ifainbriiia (iAUB. 
dutexana Harris. Two iiiitb'scribi'd corals, both typ- 
Calyplrrea t.rochiformis Lam. ically Lower Claibonn', to which 
Denlalium mimitistriatum Gabu. I liavc iiiven tin/ iiaiiics Flabel- 
Ostrca divaricata TjEA. luiii krchi and J^dniri/af/n/s biUus. 
There is not a characteristic Jackson fossil in the above as- 
semblage, while many are strictly Lower Claiborne. 
Limestone of similar character to that in which the above 
fossils occur as casts, and containing the same fossils, is found 
in Natchitoches parish, between Provencal and Robertsville, 
and one and a quarter miles south of Provencal. 
\i\ the vicinity of Victoria, Provencal, Natchitoches, and in 
southern Bienville parish, are beds of (Ks-frea aelJirfonnis^ whicii 
usually form small prairies. Unfortunately Dr. Lerch has 
been confused by this oyster; so I shall venture a correction. 
On p. 90 of his second report, in discussing tlie Jackson- 
Vicksburg groups, section No. 14 he states: 
*Tlii; si'cti(tii was inad«^ on White Oak creek. Sec. 14, T. 11 N.. H. 5 W. 
