Genus 3. 



DOGBANE FAMILY 



6. Apocynum pubescens R. Br. Velvet Dog- 

 bane. Fig. 3381. 



A. pubescens R. Br. Mem. Wern. Soc. 1 : 68. 1811. 

 Apocynum cannabinum var. pubescens A. DC. Prodr. 8: 

 440. 1844. 



Whole plant, including the pedicels and calyx, 

 densely velvety-pubescent, or the stem sometimes 

 glabrate. Branches ascending; leaves oval to elliptic, 

 obtuse or acute at the apex, strongly mucronate, 

 obtuse or obtusish at the base, the veins impressed 

 in the pubescence of the lower surface ; petioles l"-2" 

 long ; cymes dense ; calyx-segments about as long as 

 the tube of the corolla, lanceolate, acute; corolla- 

 lobes erect; follicles about 4' long. 



In dry sandy soil, Ontario to Rhode Island. Maryland, 

 Alabama, Iowa and Kansas. April-Aug. Perhaps a pu- 

 bescent race of A. cannabinum L. 



4. TRACHELOSPERMUM Lemaire, 

 Jard. Fleur. 1: pi. 61. 1851. 



Twining woody vines (some exotic species nearly erect shrubs), with opposite entire 

 deciduous leaves, and small yellow greenish or white flowers in terminal and axillary com- 

 pound cymes. Calyx small, deeply 5-parted, glandular within, the segments narrow. Corolla 

 funnelform or salverform, the tube nearly cylindric, expanded above, the lobes convolute, 

 more or less twisted. Stamens included, or short exserted ; anthers sagittate, acuminate, 

 connivent around the stigma and slightly adherent to it. Disk of 5 glandular lobes. Ovary 

 of 2 carpels; ovules numerous in each carpel; style slender, its apex thickened below the 

 narrow ring of the ovoid stigma. Follicles much elongated, slender. Seeds linear or oblong, 

 not beaked, long-comose at the apex. [Greek, neck-seed, but the seed is not beaked. 1 



About 6 species, natives of eastern Asia and North 

 America. Type species: Trachelospermum jasminoides 

 Lemaire, of eastern Asia. The following is the only 

 known North American species. 



I. Trachelospermum difforme (Walt.) A. 

 Gray. Trachelospermum. Fig. 3382. 



Echilcs difformis Walt. Fl. Car. 98. 1788. 

 Forsleronia difformis A. DC. Prodr. 8: 437. 1844. 

 T. difforme A. Gray, Syn. Fl. 2 : Part 1, 85. 1878. 



A high-climbing vine, the stems in diameter or 

 more, the twigs pubescent or glabrous. Leaves thin, 

 ovate, oval or lanceolate, acuminate or acute at the 

 apex, narrowed or rarely rounded at the base, li'-3' 

 long, \'-2.' wide; petioles 2"-^" long; peduncles slen- 

 der, shorter than the leaves; pedicels and branches 

 of the cyme bracteolate at the base ; flowers yellow 

 or cream-color, 4"-5" long ; lobes of the corolla 

 ovate, spreading, shorter than the tube; follicles very 

 slender, 5'-o/ long, scarcely 2" thick ; many-seeded. 



In moist woods and along streams, Delaware to Flor- 

 ida, Texas and Mexico, mostly near the coast, north to 

 Arkansas and 1 Missouri. June-Aug. 



Family 18. ASCLEPIADACEAE Lindl. Nat. Syst. Ed. 2, 302. 1836.* 



Milkweed Family. 



Perennial herbs, vines or shrubs, mostly with milky juice, with opposite alter- 

 nate or verticillate exstipulate leaves, and mostly umbellate perfect regular flowers. 

 Calyx inferior, its tube very short, or none, its segments imbricated or separate 

 in the bud. Corolla campanulate, urceolate, rotate or funnelform, 5-lobed or 

 5-cleft, the segments commonly reflexed, mostly valvate in the bud. A 5-lobed 

 or 5-parted crown (corona) between the corolla and the stamens and adnate to 

 one or the other. Stamens 5, inserted on the corolla, usually near its base ; fila- 

 ments short, stout, mostly monadelphous, or distinct ; anthers attached by their 



* Text revised for our first edition by Miss Anna Murray Vail, here somewhat modified. 



