Plate 6 
bi yt? 
9 ¥, . 
WAZ 
ec 

Yucca radiosa which has elongated its stem sufficiently to keep its crown abovea 
moving gypsum dune, the crest of which has passed it a few feet. The excava- 
tion has laid bare. a trunk twice the ordinary length. White Sands, New 
Mexico. (Reprinted from Publication No. 6.) 
