POLEMONIACE^. 151 



C. arvcnsis. L. Field Bindweed. A troublesome vine, 

 twining round plants in gardens and fields, with insignificant flow- 

 ers ; June. 



C. batatas. L. Sweet Potato. Sometimes cultivated in tlis 

 State ; a southern plant of great value for its roots, which are a 

 well-known luxury. A native of India and tropical America. 

 It is the potato of Shakspeare, and those who mentioned this root 

 before the common potato was cultivated in Europe. Loudon. 



Scammony, a well-known stimulant and cathartic, is obtained 

 from the roots of one species of this genus ; so diverse are the 

 properties of the various species. 



CuscUTA. L. 5. 2. 



C. Americana. L. Dodder. A singular plant, being a leaf- 

 less vine of a deep-yellow color, springing from a seed in the 

 ground, soon twining round any plant it meets with, and attaching 

 itself closely by teethlike projections, which pierce into the plant ; 

 thus it draws nourishment, and obtains a support, and soon dies at 

 the root ; it then sends out a shoot to fasten and twine in the same 

 manner, and in all cases it twines from right to left. Where it 

 is attached to other plants, it enlarges, and bears clusters of small 

 white flowers ; en banks of streams, and in shady wet places ; 

 June. This is the only species indigenous to North America. 

 Deriving its support and nutriment from other plants, it is 

 beautifully called a parasite, and is one of many parasitic plants. 



C. Europcea. L. European Dodder. Described by Beck 

 as parasitic on flax near Albany ; and occasionally to be met with 

 in this State ; a native of Britain. 



ORDER 200. POLEMONIACE^. The Greek Vale- 

 rian Tribe. 



Both floral envelopes inferior, with 5 divisions ; corolla bearing 

 the 5 stamens inserted in the middle of it, and alternating with the 

 segments ; ovary superior, 2-celled ; style simple, with a trifid 

 stigma ; capsule 1 -celled, 3-valved ; leaves simple or compound, 

 alternate or opposite. 



