394 aSCLepiadace^. (milkweed family.) 



a/mes loose, spreading, mostly longer than the leaves ; corolla (pale rose-color, 

 4" broad) open-beJI-sfiaped, with revolute lubes, the tube much loni/er than the orute 

 poitittd divisions of thi: cali/x. — Varies, with the leaves downy underneath. — 

 Borders of thickets : common northward. June, July. — Pods 3' - 4' lo>g, 

 pendent. 



2. A. cannabinum, L. (Indian Hemi'.) Stem and bnuuhes uprii/ld 

 or asccndiny, terminated by trect and dose many-jiowcicil cymes, which are usually 

 shorter than the leaves ; corolla (greenish-white) with nearly erect lobes, the tube 

 not longer than the lanceolate divibions of the calyx. — Var. glabekkimum, Z)C'. 

 Entirely smooth ; leaves oblong or oblong-lanceolate, on short but manifest 

 petioles, obtuse or rounded, or the uppermost mostly acute at l)oth ends. — 

 Var. PLBESCEXS, DC. Leaves oblong, oval, or ovate, soft-downy underneath 

 or sometimes on both sides, as well as the cymes. (A. pubescens, li. Br.) — 

 Var. HYPEEiciFOLiUM. Leuves more or less heart-shaped at the base and on 

 very short petioles, commonly smooth throughout. (A. hypericifolium, Ait.) 

 — River-banks, &c. : common. July, Aug. — Plant 2° -3° high, much more 

 upright than the last ; the flowers scarcely half the size. 



Order 80. ASCL.EPIADACE^. (Milkweed Family.) 



Plants with milky Juice, and oppofdte or whorled (j-arcbj scattered) entire 

 leaves; the follicular pods, seeds, anthers (connected with the stigma), sensible 

 properties, ffc.,just as in the last family : from which they differ in the com- 

 monly valvate corolla, and in the singular connection of the anthers icith the 

 stigma, the cohesion of the pollen into wax-like or granular masses, &c., as 

 explained under the first and typical genus. 



Tribe I. ASCLEPT ADE^E. Filaments roonadelphous. Pollen-m.asses 10, waxy, 

 fixed to the stigma in pairs liy a pland, lianging vertically. 



1. A8c]epias. Caly.x and corolla refli'xed, deeply 5-parted. Crown of 5 hooded fleshy bod- 



ies (nectaries, /..), with an incurved horn rising from the cavity of each. 



2. Acerates. Calyx and corolla reflexed or merely spreading. Crown as in No. 1, but 



without a horn inside. 



3. Enslcnin. Calyx and corolla erect Crown of 5 membranaceous flat bodies, terminated 



by a 2-cleft tail or awn. 



4. Vincdoxicum. Calyx and wheel-shaped corolla spreading. Crown a fleshy 5-10- 



lobed ring or disk. 



Tribe II. GONOLOBE.^. Filaments monadel|>hous. Pollen-masses 10, aOi.xed to the 

 stigm.i in pairs, horizontal. 



5. Goiiolobus. Corolla wlieel-shapcd. Crown a wavy-lobcd fleshy ring. 



Tribe III. PEI?II»LOCEiE. Filaments distinct or nearly so. Pollen-masses granu- 

 lar separately applied to tin- stigma. 



6. Periplocn. Corolla wheel-shaped, with 5 awned scales in the throat. 



1, ASCLEPIAS, L. Milkweed. Silkweed. 



Calyx 5-partcd, persistent ; the divi.sions small, spreading. Corolla deeply 

 5-parted ; the divisions valvate in the bud, reflexed, deciduous. Crown of 5 

 hooded bodies (nectaries, L.) seated on the tube of stamens, each containing 



