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THE 
AMERICAN NATURALIST. 
VoL. x.— OCTOBER, 1876. — No. 10. 
PLAIN, PRAIRIE, AND FOREST. 
BY PROF. J, D. WHITNEY. 
PART I. 
P spite of all that has been written in regard to the distri- 
bution of forests on the North American continent, and the 
origin of those treeless plains to which the name of prairie is 
given, the subject is one possessing a great deal of interest, since 
there is far from being any unanimity of opinion about the va- 
tious points which are involved in it. The publication of Pro- 
fessor Brewer’s map, showing in five degrees of density the dis- 
tribution of woodland within the territory of the United States, 
and which is one of the series of charts included in General Walk- 
ers Statistical Atlas, seems to offer a convenient occasion and 
excuse for reverting to the subject of the physical conditions in- 
fluencing the growth of forests. This has long been a favorite 
theme with the writer of the present article, and during the 
twenty years which have elapsed since he has published any- 
thing in regard to it, he has had many opportunities of making 
observations on the distribution of plain, prairie, and forest within 
the borders of the United States, having crossed the continent 
Several times by various routes lying between Wisconsin and 
Missouri, In these journeyings he has availed himself of the 
excellent sections afforded by the various railroad lines crossing 
the States of Indiana, Illinois, Iowa, and Missouri, accumulating 
observations which, taken in connection with those previously 
made during several years of detailed geological work in the 
heart of the prairie region, enable him to speak from personal 
knowledge of a wide extent of country, embracing, indeed, a 
8° portion of that area of mingled forests and prairies to a 
discussion of which this article is to be chiefly devoted. 
The use of the word “ prairie,” which corresponds very nearly 
“| our “meadow,” meaning a grassy, treeless, nearly level 
Copyright, A. S. PACKARD, JR. 1876. 
