224 KEY AND FLORA 



thus forming a spike. Calyx irregularly 4-5-cleft, split down 

 the lower side. Corolla swollen below, decidedly 2-lipped, the 

 upper lip arched. Stamens projecting. 



1. C. americana Wallr. SQUAWROOT, CANCER ROOT. Stems 3-6 

 in. high, yellowish or yellowish-brown. Flowers numerous, incon- 

 spicuous. Corolla dirty white or pale brown. In oak woods ; not very 

 common. 



H. OROBANCHE L. (THALESIA) 



Brownish or whitish plants, with naked scapes borne on 

 scaly, mostly underground, stems. Calyx regular, 5-cleft. 

 Corolla 5-lobed, slightly irregular. Stamens not projecting 

 from the corolla tube. 



1. 0. uniflora L. ONE-FLOWERED CANCER ROOT. Slightly cov- 

 ered with clammy down. Stems very short-branched, each with 1-3 

 1-flowered scapes 3-5 in. high. Calyx lobes lance-awl-shaped, half 

 as long as the corolla. Corolla yellowish-white, veiny, purple-tinged ; 

 palate with 2 yellow bearded ridges. Damp woods. 



2. 0. fasciculata Nutt. Stem scaly, upright, 3-4 in. high above 

 ground and generally longer than the numerous 1-flowered peduncles. 

 Calyx lobes short, triangular. Parasitic on wild species of Artemisia, 

 etc., in sandy and loamy soil N.W. and W. 



93. ACANTHACEJE. ACANTHUS FAMILY 



Herbs or shrubs. Leaves opposite or whorled, without 

 stipules. Flowers zygomorphic, usually with large bracts. 

 Calyx of 4 or 5 unequal segments which considerably over- 

 lap each other. Corolla 4-5-parted and usually more or less 

 2-lipped. Stamens usually 2 long and 2 short, sometimes only 

 2. Ovary free from the calyx. Fruit usually a capsule. Seeds 

 not winged. A large family, mostly tropical, with only a few 

 insignificant wild species in the northern United States. 



I. DIANTHERA L. 



Perennial herbs ; stem smooth. Leaves opposite, entire or 

 toothed. Flowers axillary, solitary or clustered, zygomorphic. 

 Calyx 5-parted. Corolla 2-lipped ; upper lip erect, concave, 

 entire or notched ; the lower prominently veined, spreading, 



