Obdbb OY.— ASCLEPIADAOEiE. 691 



HI. GONOLOBE^. Filaments connate. Pollinia 10, in pairs, horizontal, (c) 



c Corolla wheel-shaped. Plants twining, with cordate leaves GoNOLOBirfl, 3 



IV. 8TAPELIE.*. Filaments connate. Pollinia 10, ascending or erect, (d) 



d Crown simple, of 5 fleshy segments. Twining. Cnltlvated Hoya. 9 



d Crown double, an outer and an inner. Not twining. Cultivated Stapelia. 10 



i. PERIP'LOCA, L. (Gr. Trepi, around, nXoKog, a binding or twin- 

 ing ; from the habit of the plant.) Calyx minute ; corolla rotate, flat, 

 5-parted, orifice surrounded by a 5-cleft, urceolate corona, terminating 

 in 5 filiform awns ; filaments distinct, anthers cohering, bearded on the 

 back ; pollinia solitary, 4-lobed ; follicles 2, smooth, divaricate ; seeds 

 comous. — Twining shrubs, Fls. in umbels or cymes. 



P. Grseca L. Lva ovate, acuminate ; corymbs axillary ; cor. villous within. — ^A 

 climbing slirub, 10 — 15f long, sparingly naturalized in Western N. Y., also culti- 

 vated in gardens. Leaves opposite, 3 — 4' long, J as wide, and on petioles J' long. 

 Mowers in long, branching, axillary peduncles. Sepals minute, lanceolate, acute. 

 Petals very ' hairy within, linear, obtuse, dark purple. , FoUiclSs about 2' long. 

 Aug. § S. Bur. 



2. ASCLETIAS, L. Milk weed. (From jEsculapius, the fabulous 

 god of medicine and physicians.) Calyx deeply 5-parted ; corolla deeply 

 6-parted, valvato in asstivation, finally reflexod ; staminal corona 5- 

 leavcd, leaflets cucullate, with an averted horn-like process from the 

 base curved towards the stigma ; anthiridium (connate mass of anthers) 

 5-anglcd, truncate, opening by 5 longitudinal fissures ; pollinia (masses 

 of pollen) 6 distinct pairs fixed by the attenuated apex to a cleft gland, 

 pendulous ; follicles 2, ventricous ; seeds comous. — 71 Mostly N. Ameri- 

 can, with opposite, verticillate, rarely alternate Ivs. Umbels between 

 the petioles. 



§ Leaves linear, long and narrow (lancc-liucar in the cttUi'Bated No. 19). (*) 



* Leaves all opposite, or r.irely the highest alternate jSTos. 17 — 19 



* Leaves mostly scattered or verticillate Nos. 15, 16 



§ Leaves hroader, ovate, lanceolate, &c. Plants all native. (2) 



2 Stems dividing above into branches, corymbed or X)aniclccl Nos. 13, 14 



2 Stems simple. — Leaves sessile, cordate-cl.isping at base Nos. 11, 12 



2 Stems simple. — Leaves petiolate, the petioles often quite short. (3) 



3 Flowers (small) with a white crown and purplish-white corolla Nos. S — 10 



3 Flowers with a white crown and greenish-white corolla Nos. 5 — 7 



3 Flowers (large) with both crown and corolla purple-tinged. (4) 



4 Follicles smoothish (as are all the foregoing) Nos. 3, 4 



4 Follicles sprinkled with soft warty spines Nos. 1, 2 



1 A. corniiti Deoaisne. Simple, stout ; Iva. oblong-ovate, short-acuminate, short- 

 petiolate, downy heneath ; pedicels shorter than the leaves, densely many-flow- 

 ered ; cor. lobes ovate reflexed, 4 times shorter than tlio pedicUs ; hoods of the 

 crown ovate, obtuse, not longer than the uncinate horn. — A common, very mUky 

 herb, 3 to 4f high, in hedges and road-sides. Lvs. 5 to 8' by 2 to 3' j veiulets, 

 as in most specie.^, nearly at right angles to the midvein. Pod. stout, between 

 the petioles, bearing a globular umbel of a hundred greenish purple flowers, few 

 of which prove fruitful. Pods fuU of seeds with their long silk. Jl. 



2 A. Sullivantii Engel. Tall, very smooth ; lvs. ovate-oblong, erect, cordate, on 

 very short petioles ; hoods of the crown dbovaie, obtuse and entire at ifpex, obtusely 

 auriculate without on each side at base ; horns slender but obtuse ; folUcles with 

 scattered, warty spines. — Near Columbus, Ohio ("Sullivant." Mr. A. H. Watson). 

 Said to resemble A. cornuti in foliage and fruit, but remarkably different in its 

 crown. Petals 4 to 5" long, greenish purple. Hoods twice as long as the an- 

 thers. Jl. 



3 A. purpuriscens L. St. simple, erect, puberulent; hs. elliptical, ovaie-elUp- 

 iical or ovate, mucronate, narrowed at base into a short petiole, smooth above, 

 lomentous-pubesoent and paler beneath; ped. terminal, shorter than the leaves; 

 hoods oblong or lance-ovate, obtuse, ?ioms falcate, acute, dbi-upily lent to hori- 

 mntcU. — In hedges and thickets, N. H., Mass. to Wis. and Ey. St. 3f or more 



