The ''^fr<ifi;/rfij>Jii/ of y. TF. Li>ii island . — Vditijlia n. 227 
Pleistocenk and Recent, 
the second bottoms and alluvial valleys. 
Lower topograpliically than the Sparta sands, accompany- 
ing the larger streams, are broad flats whicli occupy an eleva- 
tion considerably higher than the present alluvial vallej^s. 
These flats are especially noticeable along the Red and Ouach- 
ita rivers. They have been well described by Dr. Lerch. 
Later than the Second Bottoms and occupying a lower 
topographic level are the present alluvial valle3's. 
The Section ok Nokthwestehn Lolisiana. 
The following is the section presented by northwestern 
Louisiana, as I have made it out: 
Recent Mluvium. 
Pleistocene Second bottoms. 
Age undetermined Sparta sands. 
i Mioceni' ( irand (iulf ^roiip. 
Tertiary , I Vicksbury- stage. 
I j Jackson stage. 
^ I'^^-'C'-'ie ; Cocksfield Ferry beds. 
Lower Claiborne stage. 
I liignitic stage. 
(.'retaceons ( ijauconitic di\isi(>n. 
I have not given estimates of the thickness of the Eocene, 
because the dip is too slight and variable to furnish reliable 
data, and no records of borings are available. 
SUMMAHY OF CONCLUSIONS. 
1. The ("retaceous of Louisiana belongs to the Glauconitic 
division, and it seems probable that its deposition was fol- 
lowed by an erosion period. 
2. (a) In Louisiana we find strata probabl}^ representing 
the Lignitic of Alabama in the extreme northwestern corner 
and at Shreveport. 
(b) The Claiborne of Louisiana, bearing marine fossils, 
represents the Lower Claiborne stage of Alabama, and it oc- 
cupies a more extensive area than has hitherto been recog- 
nized. In the southern part of the area the beds are much 
more calcareous than in the northern antl northwestern part. 
The calcareous strata are probably stratigrai)hically above 
the more glauconitic beds to the north and northwest. 
(c) The Mansfield group of Ililgard, 
