ASCLEPIADACEAE 953 
Crown prominently toothed; crest a narrow ridge or fold that 
is barely free within. . 5. V. Shortit. 
Crown merely crenulate, crest double. 6. V. obtiquum. 
Alternate divisions of the crown distinctly 2-toothed, thinner and 
narrower than the rounded somewhat crenate divisions that 
are more or less obscurely crested within : crests entire, crenate 
or bifid. 7. V. Carolinense. 
Corolla dull reddish, in the variety greenish yellow or straw-colored. 8. V. hirsutum. 
b. Corolla white: crown-divisions broad, quadrate, alternating with 5 slen- 
der deeply 2-toothed segments that much surpass the anthers. 9 
Pollinia oblong: crown 5-crenate, the divisions each 4-toothed: flowers in 
short racemes or fascicles. 10. V. Floridanum. 
B. Stems low, procumbent or diffuse, in V. productum twining: leaves small. 
Flowers solitary or 2, rarely 3 in a fascicle, never long-peduncled. 
Corolla rotately spreading. 
Crown 5-undulate, each lobe with an obtuse or subquadrate inflexed 
adnate crest, the intermediate sinus fringe-toothed : follicles muri- 
. V. Baldwinianum, 
cate and hirsute. 11. V. biflorum. 
Crown 5-parted: lobes broadly retuse, appendaged within by a thick 
fleshy ligule: follicles large and thick, muricate. 12. V. eynanchoides. 
Corolla campanulate. A : 
Crown 5-parted or apparently 10-parted, each alternate division with 
an incurved beak terminating the adnate crest within: follicles 
muricate. 13. V. pubiflorum. 
Crown saucer-shaped, with 5 internal, barely free processes terminat- 
ing the adnate crests within: follicles smooth: stem twining. 14. V. productum. 
Flowers several in a slender long-peduncled raceme: corolla rotate, small. 
Crown-lobes deeply 2-toothed, each with a slender, much longer, erect or 
; ineurved process within. : io. V. parviflorum. 
Crown-lobes emarginate or truncate, each with a slender, erect process à > 
within. ; 16. V. brevicoronatum. 
1. Vincetoxicum reticulàtum (Engelm. ) Heller. Stems high-climbing, hirsute 
with long stiff spreading hairs and a minute glandular pubescence : leaf-blades ovate- 
oblong, deeply cordate with incurved rounded and often overlapping auricles, tapering to 
a long-acuminate apex, 5-10 cm. long, glabrate or sparingly pubescent above, minutely 
puberulent and granulose beneath : peduncles as long as the petioles ( 2-10 cm. ) or longer : 
cymes 3-10-flowered : calyx with a gland at each sinus: corolla dull purplish green, 
1.4 cm. broad ; lobes oval, obtuse, scarious-margined, minutely and sparingly papillose or 
pubescent outside, green and white-reticulated within : crown an obscure ring attached to 
the base of the corolla : column slender, 1 mm. high, 5-angled, with a fleshy, rather obscure, 
angled ring approximated above that of the crown : stigma obtusely 5-angled, obscurely 
conic : pollinia pyriform : ovaries glabrate : follicles 8-12 cm. long, fusiform, long-acu- 
minate, glabrate or minutely puberulous, strongly muricate : seeds 7 mm. long, minutely 
granulose : coma 3.5 cm. long. 
In thickets and on rocky banks, Texas to Arizona and Mexico. Spring to fall. 
2. Vincetoxicum Alabaménse Vail. Stems high-climbing, sparingly hirsute with 
long rather weak hairs and a minute glandular pubescence: leaf-blades 6-15 cm. long, 
9-10 em. broad, rather thin, ovate or oblong-cordate, acuminate at the apex, the basal auri- 
cles rounded and never overlapping, the sinus narrowed at the base, sparingly puberulent 
and dark green above, lighter and more closely puberulent beneath: peduncles shorter 
than the petioles: cymes 3-6-flowered : calyx biglandulose ; lobes lanceolate, acute: co- 
rolla dull greenish yellow, 2 cm. in diameter ; lobes oval, obtuse, puberulent, and minutely 
papillose, on the outer surface, conspicuously reticulated within: gynostegium raised 
on a low broad column: crown orange-yellow, consisting of a low saucer-shaped ring at- 
tached to the base of the corolla, 5-parted, each division minutely and irregularly toothed 
or entire, appendaged within by 5 tooth-like erect crests attached to the base of the column : 
stigma white, flat, obtusely 5-angled : anther-tips white, scarious : pollinia pyriform : ovaries 
minutely puberulent: follicles 8-9 cm. long, glandular-puberulent, closely and strongly 
muricate : seeds 8-9 mm. long, obovate, granulose : coma 3.5-4.5 cm. long. 
In thickets and on sandy hillsides, Dale County, Alabama. Summer and fall. 
3. Vincetoxicum suberdsum (L.) Britton. Stems slender, twining, pubescent or 
glabrate, often with few scattered and spreading hairs: leaf-blades ovate-oblong or the 
smaller ones oblong-oval, thickish, 6-12 cm. long, 2.5-8 cm. wide, abruptly acuminate at the 
apex, sometimes a little contracted at the middle, cordate or subcordate at the base, the 
sinus shallow, rather wide and open, the basal lobes rounded: racemes few-several- 
flowered : peduncles shorter than the pedicels, which are 1-2.5 cm. long, stout and fleshy : 
calyx with a subulate gland in each sinus : corolla brown-purple or some of them yellowish, 
broadly conic in the bud ; lobes lanceolate or ovate-lanceolate, acute, pubescent or granu- 
lose within, 7-8 mm. long, erect or rotately spreading : crown an annular disk, undulately 
5- or barely 10-crenate, adnate to the corolla and but obscurely connected with the very 
short column by 5 faint ascending ridges : stigma depressed, barely 5-rayed : pollinia pyri- 
form, rounded at the base, with broad winged caudicles : follicles 10-12 cm. long, 2.5-3 
