SP Ea cee ea PRE PT a ap een Se PIE me NLS h, e SPR TREE SE TC a eee eT EET eT eee Mae Ue Pee Cre ae Loner? Serie 
7 ý X eee ne eee ee, Sa ea ae ti ete es 
1878. ] The Origin and Formation of Prairies. 299 
AN EXAMINATION OF PROF. LEO LESQUEREUX’S 
THEORY OF THE ORIGIN AND FORMATION OF 
PRAIRIES. 
BY O. P. HAY. 
OR many years past there has been no lack of literature on the 
subject of the prairies of the western states and territo- 
ries, nor any dearth of theories to account for their origin. We 
have had their existence ascribed to fire and to water; to heat 
and to cold; to all sorts of phenomena and to the lack of them. 
The forests that once clothed these regions must have been burned 
up by prairie fires—before the prairies existed. They must have 
been drowned out by the waters of vast inland lakes that once 
covered these prairie states. They must have been parched up 
up by the dryness of the climate. They must have been smothered 
by the impalpable fineness of the soil in which they grew. They 
never had an existence ; because the seeds which ought to have 
produced them must have been ground to pomace by the glaciers 
of the Age of Ice, or hopelessly buried beneath their débris. 
Prof. Leo Lesquereux, eminent in both recent and fossil botany, 
has published various papers on this subject, the latest of which 
appears in Vol. I. of the Illinois Geological Survey. In subsequent 
volumes of this excellent Survey this paper is frequently referred 
to; and certain phenomena observed in various portions of the 
state by the members of the survey corps, are cited as helping to 
establish Prof. Lesquereux’s theory. As this scientific work will 
have a wide circulation amongst geologists ; and since, on account 
of the high reputation of Prof. Lesquereux as a scientist, his 
opinions will have great weight in determining people’s opinions 
concerning an important geological feature of the West, it is 
proposed in this paper to examine the grounds upon which the 
theory has been based, and to test its correctness. For the 
writer believes that the theory is insufficient to account for all the 
facts involved—is, indeed, opposed by many of them; and that 
those examples which have been cited by the geologists as con- 
firming the theory, instead of so doing, are excellent proofs of the 
way in which prairies have wot had their origin. 
Prof, Lesquereux believes the failure of forest vegetation to 
_ occupy the praries to be due to the chemical nature of the soil, 
coupled with, as it would seem from his language, its exceeding — 
_ fineness. He believes that all our prairies and Western plains, as 
well as the plains of South America, Europe and Asia, have been oe 
