SAXIFRAGE FAMILY SAXIFRAGACEAE 
WILD HYDRANGEA 
Hydrangea arborescens L. 
The flower of our cultivated Hydrangea bushes appears 
to consist merely of a flat white calyx. It has been derived 
from the wild form and in clusters is more beautiful. 
Breeding for 
this cultivated 
race has been 
possible due to 
? the existence of 
a few such out- 
ermost flowers 
in the clusters 
of the Wild Hy- 
drangea, where 
their function 
seems to be the 
attraction of 
insects. 
The Wrage 
Hydrangea is a 
shrub 4-10 feet high, which grows along the wooded slopes of 
ravines and banks of streams from New York to Georgia and 
west to Illinois, Missouri and Oklahoma. It does not occur in 
Illinois north of La Salle county but is not uncommon in the 
central and southern portions. 
The stem is smooth or nearly so and the ovate opposite leaves 
are toothed and usually somewhat paler green beneath. 
The plant blooms in June and July and sometimes again 
in September. Frequently all the flowers are perfect. The 
8-10-ribbed calyx tube is hemispherical and remains as the 
outer covering of the fruit; the limb is 4 or 5-toothed. There are 
4 or § ovate petals, 8 or 10 stamens and 1 pistil with 2-4 styles. 
The fruit is a 15-ribbed capsule with many seeds in its 2 cells, 
and it opens by a hole between the diverging styles. 
The Gray or Pale Hydrangea, Hydrangea cinerea Small, of the 
Ohio river region differs principally in its branches, ash gray by 
means of a fine close down, and in the leaves, which are densely 
pale downy beneath. The small white flowers are in compound 
flat-topped clusters, but the outer ones are characteristically en- 
larged, showy and sterile. 
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