380 HarPER: BOTANICAL CROSS-SECTION OF MISSISSIPPI 
as I crossed the boundaries of most of the regions at the rate of 
25 to 40 miles an hour, and without ever having seen them before, 
I was unable to discern some of the distinctions that have been 
made by those who have explored the territory on foot and made 
careful studies of the stratigraphy. In the following pages the 
results of my superficial study of the more conspicuous vegetation 
of these belts, as far as I could recognize them, are set forth. 
Notwithstanding its superficiality, this has one advantage over 
previous studies of Mississippi vegetation in being quantitative. 
Under each belt or region named the geology and topography 
are briefly described, and the percentages of lime, potash, and 
phosphoric acid in the soil, taken from Hilgard’s report on cotton 
production in the fifth volume of the Tenth Census, are indicated 
in nearly every case, for purposes of comparison. Additional 
literature is cited for some of the regions. All those crossed east 
of Carrollton and Holly Springs extend southeastward into Ala- 
bama, where they have been recently described, with quantitative 
analyses of the forests of each, in my geographical report on the 
economic botany of that state (Geol. Surv. Alabama, Monograph 
8. 228 pp. June, 1913). 
The plants identified in each belt are divided first into trees, 
shrubs and herbs, and then arranged in order of abundance or 
frequency, with a number indicating how many times each was 
seen, except in the case of belts so narrow that the frequency 
numbers would be too small to have much significance. Species 
seen not more than once in a distance of fifty miles are usually 
omitted. The names of evergreens are printed in heavy type and 
those of vines in italics. 
THE REGIONS IN DETAIL 
From the Alabama line to about three miles west of Columbus, 
a distance of about 12 miles, the country is underlaid by the 
Eutaw formation, one of the divisions of the Cretaceous, but the 
surface is mostly a sandy loam of much more recent age, presum- 
ably the Lafayette.* As the railroad in this short distance crosses 
the Buttahatchee and Tombigbee Rivers and traverses a few 
* A description of this part of Mississippi by Dr. Hilgard can be found in the 
5th volume of the Tenth Census, pages 296-298. 
