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FLORA OF THE DISTRICT OF COLUMBIA. 



233 



8. Asclepias rubra L. Red milkweed. 

 Occasional in boggy places throughout our area. July. Southeastern U. S. 



9. Asclepias variegata L. White milkweed. 

 Occasional in open woods and thickets with much undergrowth, near streams. 



June-July. Eastern IT. S. 



10. Asclepias incarnate L. Swamp milkweed. 

 Frequent in swamps along and near the Potomac. May-June. Eastern N. Amer. 



11. Asclepias pulchra Ehrh. 



Abundant throughout our area, in moist soil, fields, edges of wet thickets, and 

 along streams. July-Aug. Eastern N. Amer. (A. incarnata pulchra Pers.) 

 Closely related to the last, but easily separated where, with us, the two grow together. 



129. CWVOLVTJLACEAE. Morning-glory Family. 



Stigma one, capitate, entire or 2 or 3-lobed; annuals or (J. pandurata) perennial from 



afleshyroot 1. IPOMOEA. 



Stigmas 2, linear to oblong or oval; perennials with creeping roots or rootstocks. 



2. CONVOLVULUS. 



1. IPOMOEA L. Morning-glory. 



The cultivated sweet potato and yam are forms of Ipomoea batatas Poir., and the 

 very showy and sweet-scented moonflower is /. bona-nox L. Ipomoea quamoclit L., 

 the cypress vine, with pinnate leaves, is rarely found in waste places, escaped from 

 cultivation. 



Stamens and style protruding; corolla deep red, the tube narrow.. Leaves heart- 

 shaped, entire *• L coccinea. 



Stamens and style included in the funnelform corolla tube; corolla not bright red. 

 Stigma entire or 2-lobed; ovary 2-celled; seeds 4; sepals lanceolate or ovate, acute 

 or obtuse. 

 Corolla tube purple within, otherwise white, not acutely lobed, much more than 

 twice as long as the calyx; sepals obtuse, glabrous; root perennial, often 

 large; seeds with a fringe of long brown hairs on the lateral angles. 



2. I. pandurata. 

 Corolla tube white or pinkish, acutely lobed, only twice as long as the calyx; 



sepals acute, stiff-hairy; annual; seeds glabrous -3. I. lacunosa. 



Stigma 3-lobed; ovary 3-celled; seeds 3-6; sepals long-attenuate, hairy. Annuals, 

 with glabrous seeds. 

 Leaves acuminate, entire; flowers and fruits 3-5 in a long-peduncled cluster. 



4. I. purpurea. 



Leaves acute, 3-lobed; flowers and fruits 1-3 in a short-peduncled cluster. 



5. I. hederacea. 



1. Ipomoea coccinea L. Small red morning-glory. 

 Escaped from cultivation. Aug.-Sept. Native of tropical Amer. (Quamoclit 



coccinea Moench.) 



2. Ipomoea pandurata (L.) Meyer. Wild potato vine. 

 Abundant in dry sandy and clay soils generally, trailing in the open or climbing 



in thickets. July-Aug. Eastern N. Amer. 

 The leaves of sterile plants are often 3-lobed. 



3. Ipomoea lacunosa L. 



Common in moist thickets along the Potomac and in fields and along roadsides at 

 College Park. Aug.-Sept. Eastern U. S. 



4. Ipomoea purpurea (L.) Roth. Common morning-glory. 

 Common in waste places and roadside thickets. Aug.-Oct. Naturalized from 



tropical Amer. 



