MILKWEED FAMILY. 287 



$ 2. Twining or half-scandent plants with ordinary foliage ; pod and seeds nearly as 



in Asclepias. 



Anthers with their hanging pollen masses nearly as Asclepias ; pods smooth and 

 even. 



4. ENSLENIA. Calyx and corolla 5-parted, the divisions lance-ovate and nearly erect. 



The 5 appendages of the filaments are in the form of membranaceous leaflets, each 

 bearing a pair of awns on their truncate tip. Herb. 



5. VINCETOXICUM. Corolla 5-parted, wheel-shaped. A flat and fleshy 5-10-lobed disk 



or crown in place of the hoods of Asclepias. Herbs. 



6. CYNANCHUM. Differs from the above chiefly in having 5 scales or ligules in the 



sinuses of the crown. 

 * * The 10 pollen masses horizontal, fixed in pairs to 5 glands of the stigma. 



7. GONOLOBUS. Corolla wheel-shaped ; a fleshy and wavy-lobed ring or crown in Its 



throat. 



* * * The 10 short pollen masses fixed by their base in pairs to the 5 glands of the 

 stigma, and erect. Shrubby plants, of tropical regions. 



8. HOTA. Corolla wheel-shaped, 5-lobed, thick and wax-like in appearance. Crown of 



5 thick and depressed fleshy appendages radiating from the central column. 



9. 8TEPHANOTIS. Corolla salver-shaped, the tube including the stamens, crown, etc., 



In its somewhat swollen base, the 5 ovate lobes convolute in the bud. Crown of 5 

 thin erect appendages. Stigma conical. 



* Anthers distinct, the 5 pollen masses each composed of 4 small granular masses 

 united, and applied directly to the glands of the stigma without any stalk. 

 Shrubby twiners. 



10. PEEIPLOCA. Corolla 5-parted, wheel-shaped, the divisions hairy on the upper face; 



alternate with them are the 5 small, thick scales, each bearing a bristle-shaped ap- 

 pendage. Filaments distinct, bearing anthers of more ordinary appearance than in 

 the rest of this family. Stigma hemispherical. Pods smooth. 



3. Fleshy low plants, Cactus-like, with only small fleshy scales or teeth in place of 

 leaves, on the angles of the thickened stems or branches. 



11. 8TAPELIA. Flowers large, lurid, solitary, lateral. Calyx 5-parted. Corolla 5-cleft, 



wheel-shaped ; within is a crown formed of two rings of short appendages or lobes. 

 Masses of waxy pollen 10, erect. 



1. ASCLEPIAS, MILKWEED, SILKWEED. (The Greek name of 

 jEsculapias, father of medicine. ) Flowering in summer. 2Z 



* flowers bright orange or red ; pods naked. 

 - Leaves irregularly alternate. 



A. tuberdsa, Linn. BUTTERFLY WEED, PLEURISY ROOT. Dry hills ; 

 milky juice hardly any ; stems and mostly scattered linear or lance-oblong 

 leaves hairy ; flowers bright orange. 



*- - Leaves opposite. 



A. Curassavica, Linn. Wild far S., and sparingly cult, from S. Amer., 

 as a house and bedding plant ; nearly smooth ; leaves lanceolate ; umbels 

 long-peduncled ; corolla scarlet-red, the hoods orange. 



A. paupe'rcula, Michx. Wet barrens from N. J., S. ; tall, smooth, 

 with long lance-linear leaves, one or more few-flowered umbels raised on 

 long peduncle, and red corolla with bright orange hoods. 



A. rubra, Linn. Smooth, with lance-ovate, gradually taper-pointed 

 leaves, a few many-flowered umbels on a long naked peduncle, and 

 purple-red flowers. Low barrens from N. J., S. 



