CLASS V. ORDER II. 107 



ed by the corolla. CaroUa five parted, reflexed, the segments 

 oblong. The nectary or stameneal crown is formed of five erect 

 cucullate leaves or cups, with an oblique mouth, having a small 

 incurved acute horn proceeding from the base of the cavity of 

 each, and meeting at the centre of the flower. The mass of 

 stamens is a tough, horny, somewhat pyramidal substance, sep- 

 arable into five anthers. Each of these is bordered by membra- 

 nous, reflected edges, contiguous to those of the next, and termi- 

 nated by a membranous, reflected summit. Internally they have 

 two cells. The pollen forms ten distinct, yellowish, transparent 

 bodies, of a flat and spatulate form, ending in curved filaments, 

 which unite them by pairs to a minute, dark tubercle at top. 

 Each pair is suspended in the cells of two adjoining anthers, so 

 that if a needle be inserted between the membranous edges of 

 two anthers and forced out at top, it carries with it a pair of the 

 pollen masses. Pistils two, completely concealed within the 

 mass of anthers. Germs ovate, with erect styles. The fruit, as 

 in other species, is an erect lanceolate follicle on a sigmoid pe- 

 duncle. In this it is green with a reddish tinge and doAvny. 

 Seeds ovate, flat, margined, connected to the receptacle by long 

 silken hairs. Receptacle longitudinal, loose, chaffy. — Dry soil. — 

 Woburn, Newton. — August. — Perennial. 



AscLEPiAs Syriaca. L. Common Silkwecd or Milkweed. 

 Stem simple ; leaves lance-oblong, gradtially acute, 

 downy underneath ; umbel somewhat nodding ; fol- 

 licles muricate. 



Very common byroad sides and borders of fields. Stem three 

 or four feet high, undivided. Leaves opposite, large, oblong. 

 Umbels of flowers lateral and terminal, nodding. Calyx seg- 

 ments lanceolate. Corolla green and red, reflexed quite back. 

 Nectaries red, truncated obliquely inward, and cleft Avith an 

 oblique ridge on each side the fissure, the horns moderately in- 

 curved. Mass of anthers cylindrical with black corpuscles at the 

 top of the wings, each of which draws out a pair of yellow obo- 

 vate pollen masses. Pods or follicles oblong, acute, covered with 

 soft spinous projections. They contain large quantities of a fine 



