210 American Midland Naturalist Monograph No. 2 



1. Corolla about 2 cm. long; bracts small, attached some distance below the 

 flower; fields and waste places, common; nat. from Eur. June-Sept. Field 

 Bindweed C. arve7isis L. 



3. Qu AMOCLIT Moench — Red Morning-glory 



Q. coccinea (L.) Moench. Fields and roadsides, occasional; native of trop. 

 Am. July-Oct. 



4. Ipomoea L. — Morning-glory 



(Pharbttis Choisy) 



1. Calyx-lobes obtuse, glabrous, elliptical, 1.5-2 an. long; corolla 5-8 cm. long, 

 white, the tube purple within; leaves ovate, cordate; stem glabrous; cap- 

 sules ovoid, 2-4-seeded; seeds hairy; root perennial, often large; fields, 

 thickets, and waste places throughout 111. June-Sept. Wild Sweet-potato 



/. pandurata (L.) G. F. W. Mey. 



1. Calyx-lobes acute or attenuate, pubescent; s':cm pubescent; capsules globose; 

 seeds glabrous; plants annual. 

 2. Calyx-lobes elliptical or lanceolate, acute or acuminate. 



3. Calyx 10-12 mm. long, the lobes ciliate, acuminate; corolla 1.5-2.5 cm. 

 long, white; leaves entire or 3-angled; fields and along streams, s. III., 

 extending northw. to Peoria and Hancock counties. July-Oct. Small- 

 flowered Morning-glory /. laciinosa L. 



3. Calyx 12-16 mm. long, hirsute toward the base; corolla 5-7 cm. long, 

 purple, pink, variegated, or white; leaves ovate, cordate, rarely 3- 

 lobed; fields and waste places; native of trop. Am. Aug. -Oct. Com- 

 mon Morning-glory /. purpurea (L.) Roth 



2. Calyx-lobes linear-lanceolate, attenuate, copiously hirsute below, 1.5-2.5 

 cm. long; corolla 2.5-4 cm. long, purple; leaves 3-lobed; fields and 

 waste ground; native of trop. Am. July-Oct. Ivy-leaved Morning-glory 

 /. hederacea Jacq. 



5. CUSCUTA L. — Dodder 

 1. Sepals separate. 



2. Flowers cymose, pedicelled; scales short; bracts entire; on various herbs, 



s. 111. Aug.-Sept C. cuspidata Engelm. 



2. Flowers sessile in dense clusters; bracts serrulate. 



3. Styles as long as the ovary; bracts few, broad, appressed; parasitic on 



various shrubs and herbs. July-Oct C. covipacta Juss. 



3. Styles longer than the ovary; bracts numerous, narrow, their tips re- 

 curved; chiefly on Solidago, Aster, Helianthus, and other genera of 

 Compositae C. glonicrata Choisy 



1 . Sepals united below into a synsepalous calyx. 

 4. Flowers nearly sessile. 

 5. Corolla-scales fimbriate. 



6. Flowers 1.5 mm. long; calyx-lobes overlapping, forming angles at the 

 sinuses; seeds depressed-globose, 1 mm. long; on various herbs and 

 shrubs. lune-Oct. fC. arvensis Beyr.] C. pentagona Engelm. 



