1892. ] The Flora of Chicago and Vicinity. 251 
lake flora sparingly, being found by Wolf Lake just east of 
the Indiana line. The soil is sandy and of little strength, so 
that all the trees are small. They are scattered over an 
area of a few acres, and are quite isolated in their position. 
Southwest of the city this oak occurs again on the Desplaines 
below the mouth of Flag Creek. — In the rich soil of the 
bottom land it makes a large tree. These are the only locali- 
ties near Chicago where it is at present known to grow. 
About fifty miles south it is not uncommon by the Kankakee 
tiver. Q. imbricaria comes a little further north along the 
Desplaines and Flag Creek, thence extending south to Joliet 
and beyond. 
7. Eleocharis quadrangulata R. Br.—Abundant in the 
Shallow water of Wolf Lake, but within the city limits. In 
the Manual its range is not extended west of Michigan. It 
has been found in Illinois and Missouri in the vicinity of St. 
Louis. In Wolf Lake it very fully occupies the ground 
where it grows, preserving the character Elliott gives it in 
his “Sketch,” (I, 79.) ‘‘In rice fields it becomes a very in- 
Jurious intruder, as its thick creeping roots occupy the ground, 
and permit nothing to grow where they extend.” 
8. Eleocharis olivacea Torr.—While looking the past season 
for E. capitata R. Br., since the only station where it had hither- 
tobeen seen, at Whitings, Ind., seemed likely to be destroyed 
by the works of the Standard Oil Company, I found it again 
about a mile from the original locality. The new station is 
on the borders of Lake George. With it 2. ol/vacea was also 
found. Both are quite plentiful in patches in the wet, marly 
sands in which these shallow lakes abound, since the fresh 
Water mollusks are so prevalent that their comminuted shells 
erm a whitish marl. Such a soil affects the flora to some ex- 
a It is in this fine mud, a mixture of sand and calcareous 
sited that these two species of Eleocharis grow. Both are 
se 
Y cespitose, forming small tufts. The stems of £. capé- 
are erect or ascending, from half an inch to seven of 
inches high, and form fibrous, annual roots, while those 
- olivacea are diffuse or subdecumbent, from two to four 
