Copyright 1953,
by Denver Museum of Natural History, Denver, Colorado
Lithographed in the United States of America
by Bradford-Robinson Printing Company,
Denver, Colorado
_Acknowledgments:_
The original color films used for the plates on pages 15 and 26, were
heretofore reproduced in different form in “American Wild
Flowers”—Moldenke, published in 1949 by D. Van Nostrand Co., New York,
with whose permission they are again reproduced here.
The pen and ink diagrams and sketches on pages 3, 60, 61, 62 and inside
back cover, were prepared by Mary Chilton Gray, of the staff of Denver
Museum of Natural History.
Lily Family
Yucca or Spanish Bayonet, _Yucca glauca_, NUTT.
⇐FRONT COVER
Flowers, closely arranged along a tall woody bloom stalk, are each
formed by 6 petals and sepals (perianth segments) surrounding a large
fleshy pistil. The 3 outer segments often have mahogany brown shading on
the back, the 3 inner are creamy white, or greenish white. They look
like drooping bells in the daytime, but spread to a total width of 3 to
4 inches when fully open in late evening. Pollination is accomplished
only by the deliberate work of a _Pronuba_ moth. Total height of plant,
including blossom stalk, is about 4 feet; leaves narrow, stiff and
yellowish green, with a sharp spine at tip. Grows on plains,
particularly in sandy areas, and extends into foothills. Blooms
June-July.