BIG SPRING PRAIRIE. 15 
eleven White Oaks, four Red or Black Oaks, two Shin- 
gle Oaks, three Hickories, and a large Elm, the last 
was situated in a slight depression, and is over two feet 
in diameter. 
The principle shrubs of the xero-mesophytic area 
are Corylus Americana, Walt. (Wild Hazel-nut); Rhus 
aromatica, Ait (Fragrant Sumac); Crataegus, (several 
species); and Rhus glabra L. (Upland or scarlet sumac); 
while the following are quite common: Hamamelis vir- 
giniana L,. (Witch hazel); Rhus radicans L. (Poison 
Ivy); Viburnum prunifolium L. (Black haw); Vibur- 
num pubescens (Ait) Pursh. (Downy leaved arrow- 
wood); Rubus villosus ait. (High-bush blackberry); Ru- 
bus occidentalis L. (Black raspberry); Ribes Cynobasti 
L,. (Wild Goose berry); Rubus Canadensis L. (Dew- 
berry); Vitis sp? Ptelea trifoliata L. (Shrubby tree-foil); 
Viburnum acerifolium L. (Maple-leaved arrow-wood); 
Celastrus scandens, L. (Climbing Bittersweet); Smilax, 
several species; Parthenocissus quinquefolia (L.) 
Planch (Virginia Creeper); and Enonymous atropur- 
purens, Jacq. (Wahoo, or burniug bush). Three of the 
above species Rhus aromatica, Ptelea trifoliata, and 
Crataegus were found growing, in the Summer of 1902, 
on a sand dune along the shore of Lake Michigan, 
thus proving the xerophytic capabilities of these spec- 
ies. Frequently by the lagging behind of effects, xero- 
phytic plants will cling to an area for a considerable 
time even after the conditions have changed to the 
xero-mesophytic or to the mesophytic. 
On the median plane and the drainage valleys, 
most of the above species also occur, but not so com- 
monly; while Benzoin benzoin (L.) Coult. (Spicebush), 
Cornus, several species; Rosa sp?; and Xanthoxylum 
Americanum Mill. (Prickly Ash) are quite abundant. 
The common or characteristic herbaceous plants 
of the xero-mesophytic area are Antennaria plantagini- 
folia (L) Rich. (Plantain-leaf Everlasting), which fre- 
