346 Karl M. Wiegand and Arthur J. Eames 



Frequent on the hills and ravine crests w., s., and e. of Ithaca, along the cliffs 

 of Cayuga Lake, and in the sand n. of the lake; rare or absent in the McLean 

 region and on the clays and richer soils back from the lake shores. 



N. H. to Ont. and Minn., southw. to N. C. and Ark. ; rare on the Coastal Plain. 



Forms with leaves all in pairs are occasional. 



2. Cynanchum L. 

 1. C. Vincetoxicum (L.) Pers. 



Low sandy woods and banks ; rare. Tune-Sept. 



Big Gully, 1919 (L. F. Randolph) ; Big Gully Point, 1918; abandoned quarry n. e. 

 of Farley Point; wood road e. of Westbury Bog. 



Mass. and Vt. to Pa. and Ohio. Introduced from Eu. 



The plants included above agree with European and American specimens of C. 

 Vincetoxicum as to size of flowers, length of sepals, glabrous corolla, and petioles 

 pubescent on the under side as well as on the upper side, but they have dark purple 

 flowers. 



105. CONVOLVULACEAE (Morning-Glory Family) 



a. Plants with green leaves; corolla large, funnel-form, showy. 



b. Stigmas capitate; calyx without subtending bracts. [Ipomoea] 



b. Stigmas linear or oblong; calyx with or without large bracts. 



1. Convolvulus 

 a. Plants without green leaves, yellowish or flesh-colored, parasitic; corolla very 

 small, campanulate, short-cylindrical or globose, whitish. 2. Cuscuta 



[Ipomoea L.] 



a. Corolla almost or quite salver-form, red ; stamens and style exserted. 



[/. coccinea] 



a. Corolla funnel-form, color purple, blue, or white; stamens and style included. 

 b. Leaves 3-lobed ; flowers 2.5^.5 cm. long. [/. hederacea] 



b. Leaves entire; flowers 4.5-7 cm. long. [/. purpurea] 



[I. coccinea L. 



" Was growing, in 1885, in a large mass by the old road crossing the marsh to 

 the steamboat landing " (D.) ; not seen in recent years. 

 S. w. U. S. and tropical Am. Naturalized northeastw.] 



[I. hederacea Jacq. (/. Nil of Cayuga Fl.) 



" Occasionally seen with the preceding |7. purpurea} " (D.) ; not found recently. 



Waste and cultivated ground : Me. to Nebr., southw. to Fla. and Mex. Intro- 

 duced from tropical Am.] 



[I. purpurea (L.) Lam. Common Morning-Glory. 



Springs up frequently in waste places and about garbage dumps, but is not 

 established. July-Aug. 



Escaped from cultivation in e. N. A. Introduced from tropical Am.] 



1. Convolvulus (Tourn.) L. 



a. Calyx inclosed by two large bracts ; stigmas oval or oblong. 



b. Stem low, erect ; leaves broadly oblong ; petioles not more than one-fourth 



the length of blade ; bracts narrowed at base. 1. C. spithamaeus 



b. Stem twining or trailing ; leaves triangular-ovate or oblong-ovate ; petioles 



longer ; bracts broad and usually cordate at base. 



