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species to Gibson, Knox and Posey counties. The species is mainly coastal, 
occurring along the Atlantic and Gulf coasts, finding its way into the 
interior along the valley of the Mississippi and its tributaries. The oceur- 
rence of this coastal species, and of others which might be cited, in regions 
so markedly interior, suggests the thought that they entered our flora at 
the time when the great northward arm of the Gulf of Mexico practicaily 
divided the area of the United States into distinct eastern and western 
regions. A comparison of the boundaries of this arm of the Gulf of Mexico 
with the distribution of many species of plants gives striking support to 
such an explanation. In Indiana, the species is not ordinarily separated 
from the Burr oak (Quercus macrocurpa Michx., which it closely resembles. 
The Cow or Basket Oak (Quercus Michaurii, Nuttall) so far as our 
records go occurs only in Knox and Gibson counties, where it is found in 
low, rich bottom lands. This restriction of area may be due in part to the 
close resemblance in size and habit of this species to the Swamp White 
Oak (Quercus bicolor Willdenow) and a consequent failure to distinguish it 
from that species. This oak, also, is more or less coastal in its mass dis- 
tribution, finding its way into the interior along the valley of the Missis- 
sippi; while the Indiana localities represent its northeastern limit the 
species maintains its normal size and habit. Its ability to maintain a foot- 
hold in localities often covered with water serves to explain its persistence 
in the counties named. 
The Spanish Oak (Quercus falcata Michaux) is reported definitely from 
Knox, Gibson and Posey counties, with an additional citation from Foun- 
tain County (Brown) which the writer has not had opportunity to verify. 
Some difficulty arises in this case because of the question of the validity of 
the species. According to Sargent Quercus falcata is separable into two 
species, Quercus digitata Sudworth, and Quercus pagodefolia Ashe. <Ac- 
cording to Gray’s Manual’ Q. falcata is found’ on dry or sandy soil; upon 
the authority of Sargent Q. digitata grows in similar soils on dry hills; 
while Q. pagodefolia occurs on rich bottom lands and alluvial banks of 
streams. In Indiana the form in question “is usually found in low ground, 
associated with Quercus bicolor, Q. palustris, Q. Schcneckii, Q. stellata and 
Q. velutina, The whole of the township is low.’’ The habitat as well as 
considerations of distribution would seem to indicate the species to be 
VY. pagodefolia Ashe instead of Q. falcata Michaux. In the Proceedings of 
4Gray’s New Manual of Botany. Seventh Edition. p. 343. 
5Deam. Op. cit. 207. 
