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PLANTS OF YELLOWSTONE NATIONAL PARK 
Myriop hyllum verticillatwn is similar, but the leaves are mostly 
in threes or fours, and those that subtend the flowers are also pin- 
nately divided. 
The genus is commonly known as parrotfeather. 
PARSNIP FAMILY (AMMIACEAE OR TJMBELLIFERAE) 
This is a large family and contains some valuable edible plants, 
such as the parsnip and the carrot, and others, such as the water 
hemlock, that are deadly poisonous if eaten. Most members of the 
Figure 71.—Cow-parsnip. White. Photograph by Joseph S. Dixon, National Park Service. 
family are herbs with hollow stems and alternate leaves. The leaves 
are usually compound and often 2 or 3 times compound. The ovary 
is below the other parts of the flower and there are usually 4 calyx 
teeth, 5 petals, 5 stamens and 2 styles. The fruits are dry and 
may be flat or cylindrical, but in any case consist of two one-seeded 
parts which are attached face to face and the backs of which are 
provided with five or more ribs and sometimes with wings. The 
flowers are so nearly alike in many members of the family that often 
it is necessary to have mature fruits in order to make identification 
certain. However, the few that are common in the park can be dis¬ 
tinguished very largely on the basis of leaf characters. 
