OROBANCHACEAE 565 



OROBANCHACEAE 



Flowers all complete and perfect. 

 Calyx 2-5-toothed. 



Calyx about equally 5-cleft; no bracts on pedicels or calyx. 1. Thalesia. 

 Calyx unequally toothed, or split on both sides; flowers 



bracted. 2. Orobanche. 



Calyx spathe-like, split on the lower side, 3-4-toothed on the 



upper. 3. Conopholis. 



Lower flowers cleistogamous, fertile; upper complete, mostly sterile. 4. Leptamnium. 



i. Thalesia Raf. 



1. T. uniflora (L.) Britton. In woods and thickets: Newf. to 



B. Col., Va., Ohio., Tex. and Cal. Parasitic. 



Conn. Throughout the area, increasing northward. 



N. Y. Rare and local on L. I. and S. I., increasing northward. 



N. J. Occasional in Burlington, Monmouth, Ocean and Mercer 



counties, thence increasing northward; not in the pine-barrens. 

 Pa. Throughout the range. 



Tertiary, o: Cretaceous, rare: Older Formations, increasing 

 northward. 117-220 days. Sea level-3,500 ft. 



2. Orobanche [Tourn.] L. 



Calyx split on both sides; stem simple. 1. 0. minor. 



Calyx 4-toothed; stem mostly branched. 2. 0. ramosa. 



i. O. minor J. E. Smith. Parasitic on the roots of clover: N. Y. 

 to Va. Naturalized from Europe. 

 Scattered in most parts of our range from New York southward. 



2. O. ramosa L. Parasitic on the roots of tomato, hemp and 



tobacco: N. J., 111., Ky. Adventive from Europe. 

 On tomato, New Brunswick, N. J. 



3. Conopholis Wallr. 

 1. C. americana (L. f.) Wallr. In rich woods, usually at the 

 bases of oak trees: Me. to Mich, and Fla. Rare. 

 Conn. Known only from Plainville, Southington, Guildford and 



New Haven. 

 N. Y. Known definitely only from S. I. and from Bronx and 



Westchester counties. 

 N. J. Known definitely only from Camden, Hunterdon, Essex and 



Bergen counties, the latter station on the Palisades opposite 



Yonkers, rare. 

 Pa. Bucks, Delaware and Chester counties. 



A rare and local plant. 



