ORDER 97. ASCLEPIADACE^E. 591 



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



c Corolla wheel-shaped. Plants twining, with cordate leaves ............. GONOLOBCS. S 



IV. STAPELIE.dE. Filaments connate. Pollinia 10, ascending or erect, (d) 



d Crown simple, of 5 fleshy segments. Twining. Cultivated ................... HOYA. 9 



d Crown double, an outer \nd an inner. Not twining. Cultivated ........... STAPELIA. 10 



1. PERIP'LOCA, L. (Gr. Trept, around, TT/IOKO^, 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. Graeca L. Lvs. ovate, acuminate; corymbs axillary; cor. villous within. A 

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

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

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

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

 Aug. S. Eur. 



2. ASCLE'PIAS, L. MILK WEED. (From Esculapius, the fabulous 

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

 5-parted, valvate in aestivation, finally reflexed; staminal corona 5- 

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

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

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

 of pollen) 5 distinct pairs fixed by the attenuated apex to a cleft gland, 

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

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

 the petioles. 



Leaves linear, long and narrow (lance-linear in the cultivated No. 19). (*) 



* Leaves all opposite, or rarely the highest alternate ........................... Nos. 17 19 



* Leaves mostly scattered or verticillate ....................................... Nos. 15, 16 



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



2 Steins dividing above into branches, corymbed or panicled .................... Nos. 13, 14 



2 Stems simple. Leaves sessile, cordate-clasping at base ....................... Nos. 11, 12 



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



3 Flowers (small) with a white crown and purplish- white corolla ........... Nos. 8 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. cornuti Decaisne. Simple, stout ; Ivs. oblong-ovate, short-acuminate, short- 

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

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

 crown ovate, obtuse, not lefager than the uncinate horn. A common, very milky 

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

 as in most species, nearly at right angles to the midvein. Fed. stout, between 

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

 of which prove fruitful. Fods full of seeds with their long silk. JL 



2 A. Sullivantii Engel. Tall, very smootfi; Ivs. ovate-oblong, erect, cordate, on 

 very short petioles; hoods of the crown obovaie, obtuse and entire at apex, obtusely 

 auriculate without on each side at base ; horns slender bat obtuse ; follicles with 

 scattered, warty spines. Xear 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. purpurascens L. St. simple, erect, puberulent; Ivs. elliptical, ovate-ellip- 

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

 tomentous-pubescent and paler beneath ; ped. terminal, shorter than the leaves ; 

 hoods oblong or lance-ovate, obtuse, horns falcate, acute, abruptly bent to hori- 

 zontal. In hedges and thickets, N. H., Mass, to "Wis. and Ky. St. 3f or more 



