MILKWEED FAMILY 101 



APOCYNUM Linne 1753 DOGBANE 



(Gr. name of the dogbane; apo, from, kyon, kynos, dog) 

 PL 17, fig. 4. 



Sepals 5, united, petals 5, white to pink, united into a bell-shaped 

 tube, bearing 5 triangular scales, alternating with the 5 stamens, ovary 

 of 2 carpels, stigma obscurely 2-lobed, fruit of 2 long terete follicles, seeds 

 with a hairy apex ; flowers in terminal and axillary cymes ; leaves oppo- 

 site, entire; perennial. 



1. Corolla pink or pinkish, rarely white, with tube 



longer than calyx and lobes turned back A. androsaemifolium 



2. Corolla white or greenish, tube shorter than calyx 



and lobes erect A. canndbinum 



ASCLEPIADACEAE MILKWEED FAMILY 



Sepals 5, united, petals 5, united into a bell-, urn-, saucer-, or funnel- 

 shaped corolla, a 5-lobed or 5-parted crown between the corolla and the 

 stamens and united to one or the other, stamens 5, inserted on the corolla, 

 usually near its base, filaments short, stout, ovary of 2 carpels, styles 2, 

 short, connected at the summit by the shield-shaped stigma, fruit 2 folli- 

 cles, flowers perfect, regular, in umbels; perennial herbs, vines or shrubs, 

 mostly with milky juice and opposite, alternate or whorled leaves. 



1. Hoods of the crown without horn or crest ACERATES 



2. Hoods with horn or crest within 



a. Leaves mostly opposite or whorled ; hoods with 



an incurved horn ASCLEPIAS 



b. Leaves alternate; hoods with a crest ASCLEPIODORA 



ACERATES Elliott 1817 ACERATES 



(Gr. 0^, without, keras, horn, from the hornless hoods) 



PL 17, fig. 5. 



Sepals 5, united, petals 5, green or purplish, united, turned back, 

 crown-column very short, crown of 5 somewhat pitcher-shaped hoods, 

 stamens 5, pollen masses solitary in each sac, oblong, hanging, stigma 

 5-lobed; flowers in umbels, terminal or short-stalked, leaves thick, alter- 

 nate or opposite ; perennial herbs. 



1. Flower clusters on stalks 1-5 cm. long; leaves 



very long and narrow A. auriculdta 



2. Flower clusters stalkless or nearly so 



a. Hoods 3-toothed at tip ; leaves elongated, linear A. angustifolia 



