MILKWEED FAMILY. 289 



minal and solitary or corymbed umbels ; pods thick, ofteu with some soft 

 tubercle-like projections. Prairies, 111. to Tex. and S. C. 



3. ACERATES, GREEN MILKWEED. (Name from the Greek,, 

 means xcithout a horn, i.e. none to the hood-like appendages, in which 

 it differs from Asclepias.) Flowers green or gi-eenish, in summer. 2Z 



A. viridifl6ra. Ell. Dry sandy or gravelly soil ; soft-downy or smooth- 

 ish, l°-2° high ; leaves varying from oval to linear, mostly opposite ; 

 globular umbels nearly sessile; flowers short-pediceled, nearly },' long 

 when open ; hoods not elevated above the base of the corolla. 



A. longifdlia, Ell. Low barrens Ohio, W. and S.; rather hairy or 

 roughish, l°S° high, with very numerous, mostly alternate, linear leaves ; 

 flowers smaller and on slender pedicels, the umbel peduncled ; hoods ele- 

 vated on a short ring of filaments above the base of the corolla. 



4. ENSLENIA. (Named for A. Enslen, an Austrian traveler.) 2/ 



E. dlbida, Nutt. Climbing, 8°-12° ; smooth, with opposite, heart-ovate, 

 long-petioled leaves, and small, whitish flowers, in raceme-like clusters on 

 axillary peduncles, all late summer. River banks, Penn., S. and W. 



5. VINCETOXICUM. (laatin: binding, poison.) % 



V. nigrum, Moench. A low-twining, smooth weed from Eu., escaping 

 from gardens E.; leaves ovate and lance-ovate; flowers small, brown- 

 purple, rather few in axillary umbels, in summer. 



6. CYNANCHUM. {Grefik, me&mng dog poison.) 



C. acuminatifolium, Hemsley (or Vincetuxicum acuminXtum). Mos- 

 quito Plant, so called, because small insects are stuck fast in the clefts 

 of the crown ; flowers white and pretty, in axillaiy clusters ; leaves 

 lanceolate or ovate-lanceolate and acuminate ; 2°-3°, with a twining 

 tendency. Japan. % 



7. GONOLOBUS. (Greek: angled pod.) Ours are twining herbs, 

 along river banks, with opposite, heart-shaped, petioled leaves, and 

 corymbs or umbels of dark or dull-colored small flowers, on peduncles 

 between the petioles. The following are the commonest. 11 



Q. l^vis, Michx. Smooth or only sparingly hairy, the yellowish-green 

 flowers and the longitudinally ribbed pods smooth. Va., S. and W, 



G. obliquuB, R. Br. Hairy, somewhat clammy ; flowers minutely 

 downy outside, long and narrow in the bud, dull crimson-purple within, 

 the strap-shaped or lanceolate divisions i' long; pods ribless, warty. 

 Penn., S. and W. 



G. hirstitus, Michx. Differs from the last in its short-ovate flower 

 buds, the oval or oblong divisions of corolla only about V long. Va., S. 

 and W. 



8. HOYA, WAX PLANT. ( TAowias ^oy, an English gardener.) H 



H. carndsa, R. Br. Well-known hou.se plant from India ; with rooting 

 stems, thick and fleshy oval leaves, umbels of numerous flesh-colored or 

 almost white flowers, the upper surface of corolla clothed with minute 

 papillae. 



9. STEPHANOTIS. (Greek : crown and ear, referring to the appen- •' 

 dages of the stamens. ) 2/ 



S. iloribunda, Brong. Madagascar Jasmine. A fine hothouse twiner, 

 very smootli, with opposite, oval or oblong, thickish leaves, and lateral 



gray's F. F. & G. BOT. — 19 



