THE 
AMERICAN GEOLOGIST. 
Vol. XV. APRIL, 1895. No. 4. 
THE STRATIGRAPHY OF NORTHWESTERN 
LOUISIANA.* 
By T. Waylaxd \'aughax, Washington, D, C. 
(Plate I X.J 
CONTENTS. 
Page 
Introduction: .^rea defined 205 
Cretaceous 206 
Tertiary 20S 
Eocene, characters and distribution 20S 
Lignitic stage 2o<) 
Lower Claiborne stage, including discussions of the "Mansfield group," the 
"Arcadia clays," the small prairies or meadows of Winn parish, etc., the "Up- 
per l.ignitic"' of Dr. Lerch, and the red clays and red sandy clays in the vi- 
cinity of Mt. Lebanon and Arcadia 210 
The Cocksfield Ferry beds 220 
The Jackson and Vicksburg stages 221 
Miocene: the Grand Gulf group 224 
Age undetermined: Sparta sands 225 
Pleistocene and Recent 227 
Second Bottoms and .\lluvial \'alleys 227 
The Secticm of Northwestern Louisiana 227 
Summary of Conclusions 227 
Intkoduotion : Akea defined. 
The following paper contains a resume of the results of a 
somewhat protracted study by the author of that portion of 
*Publislit'd by pi-rmissioii of the Director of the V. S. (irojugical Sur- 
vey. 
In this work I have received courtesies and assistance from several 
irentiemen to whom I desire to e.vpress my obiijralions. To Dr. Otto 
Lerch 1 am indebted for many su^'iicslions wliile in Ihe field witli him. 
He also snbmilled to me for stiidv Ihi- collection of the Loiiisian.-i (ieol. 
Survey. To Dr. Wm. H. Dall. Prof. Anjrelo Heilprin. Mr. IL A. PUs- 
bry. Dr. C. E. lieecher, and I'rof. R. P. Whitfield, I ow.- my thanks for 
access to tlie collections under their charj,'e. To Dr. Dai! and Jlr. I{. T. 
Hill I am indebted for advice. Mr. (J. D. Harris lias ri'iidi'i-t'd me irre.-il 
assistance in helping,' me determine some of the fossils, esiiecially those 
whiclt he has named, the descriptions of vvhicli have not yet appeared 
in prim. To Dr. Hobt. T. .lackson. Prof. N. S. Shaler a^ld Mr. L. S. 
(Jrisvvold of Har\ard T'niversitv I am thankful for ad\ice. 
