U. S. GEOLOGICAL SURVEY 



PROFESSIONAL PAPER 91 PLATE V 



.1. CALCAKEOUS CONCRETIONS IN SANDS OF THE WILCOX GROUP, 



SHREVEPORT, LA. 



I. ■•■ y.. vx- ,. 





:v.- 



Ss^- 



-*W1-T 





B. LIGNITE BALLS OR CONCRETIONS IN SANDS OF THE WILCOX 

 GROUP AT LEIGH, TEX. 



