FAMILIES OF PLANTS 
93 
Onagra strigosa .—This plant grows 1 to 3 feet high and is more 
or less hairy. The leaves are alternate and vary greatly as to size 
and shape, but are usually somewhat lance-shaped and 2 to 4 inches 
long. The yellow flowers are quite numerous but not many open at 
the same time. They open in the evening and close after the sun 
rises the next day. 
Sweet evening-primrose ( Anogra nuttallii) grows 2 to 4 feet tall and 
is very leafy. The leaves are linear and entire or nearly so. The 
Figure 70.—Moonrose. White. Photograph by Dr. Harvey E. Stork. 
large, white flowers are borne in the axils of the leaves and bloom in 
the daytime rather than at night. 
WATER MILEOIL FAMILY (HALORAGIDACEAE) 
A small family of water plants with whorled leaves and incon¬ 
spicuous, greenish flowers. 
Marestail (Hippuris vulgaris ) is usually found in shallow ponds 
or on muddy banks. The stems are smooth, slender and 8 to 20 
inches high and the leaves are linear and entire and occur in whorls 
of 8 to 12. The solitary flowers are inconspicuous. 
Myriophyllum spicatum .—The leaves are produced in whorls of 
4 or 5 and all except those that serve as bracts for flowers are pin- 
nately divided into hairlike divisions. 
785717°—48-7 
