HOODED LADIES-TRESSES 
Ibidium strictum (Rydberg) House 
Hooded ladies-tresses is later in blooming than most of our native 
otchids, and often delays flowering until the end of summer. It grows 
in moist or swampy places, in low meadows or near the borders of 
streams. It is a very sweet-scented plant and is often abundant whete 
congenial soil and moisture conditions exist. Cross-pollination of the 
flowets is insuted by their intricate structure, and bees carry the pol- 
len from one flower to another. Darwin's interesting observations on 
this process have been recorded in great detail, and he and Asa Gray 
had an extensive correspondence upon the subject. | 
The plant has a wide range, extending in one form or another from 
Pennsylvania to Newfoundland, New Mexico, California,and Alaska. 
Perhaps mote than one species is included in this citation of tange, 
as those from the east and from the west look rather dissimilar. 
The flowets sketched were obtained in the Siffleur River Valley, 
fifty miles by trail north of Lake Louise, Alberta, at an altitude of 
4,500 feet. 
PLATE 356 
