FAMILIES OF PLANTS 
45 
manufacture food like a green plant. The underground stem is 
always infested by a fungus, and apparently the coralroot is a 
parasite on the fungus. The three species are quite similar but can 
be distinguished in the following manner: 
Lip deeply 3-lobed. Corallorhiza multiflora. 
Lip with a small tooth or lobe on either side. Corallorhiza innata. 
Lip entire. Corallorhiza striata. 
Figure 31.—Coralroot. Brownish purple. Photograph by A. R. Sweetser. 
NETTLE FAMILY (UETICACEAE) 
A family of varying characteristics, some members being thickly 
beset with stinging hairs. Quite a large family but represented here 
only by the Narrowleaf nettle (TJrtica gracilis ). This is a tall, slen¬ 
der plant sparingly beset with stinging hairs and bearing loosely 
clustered spikes of small, greenish, imperfect flowers. The leaves are 
opposite, ovate or lance-shaped, petioled, toothed, and 3- to 5-veined. 
The staminate flowers have 4 stamens while the pistillate have a 
single pistil. The fruit is an akene. 
WILLOW FAMILY (SALICACEAE) 
A family of trees and shrubs with simple, alternate leaves. The 
most common of our broad-leaved trees belong to this family. 
785717°—48--4 
