Periploca. CII. ASCLEPlADACEiE. 461 



staminal corona 5-leaved, leaflets without horns, concave, appressed to 

 the angles of the antheridium ; pollinia 5 pairs, pendulous ; follicles 

 smooth or muricate. — % Herbs differing from Asdepias only in the ab- 

 sence of the horn-like processes of the corona. Lvs. mostly opposite. 



1. A. viRiDiFLORA. Ell. rand A. lanceolata. Ives, and Isf.edit. Asclepias. 

 PursL) — Saftruticosp. at base, pubescent above; lvs. elliptical, varying to 



oblong and lanceolate, briefly petiolate, scabrous above and on the margin, to- 

 mentose-pubescent beneath; umbels sessile, globose, many-flowered; pedicels pn- 

 bescent ; pet. ovate, reflexed ; segments of the corona erect and adnate to the 

 antheridium. — Can., Conn, to Ark., in dry, stony soils. Stem 2 — 3f high, as- 

 cending and often branched at base, clothed with dense, close hairs. Leaves 

 3 — 6 or 8' long. ^ — ^ as wide, obtuse or acute, or even acuminate, scarce- 

 ly petiolate. Flowers green, small, inelegant, in 2 or 3 small, subglobose um- 

 bels. July. — The plant varies greatly in respect to its leaves. 



2. A. LONGiFOLiA. Ell. Lon^-leaved Acerates. 



Scabrous -puberulent ; st. ascending, simple ; lvs. alternate, numerous, 

 linear and lance-linear, subsessile, acute ; umbels half as long as the leaves, 

 numerous, many-flowered, pubescent, axillary, pedunculate ; corona scales 

 shorter than the antheridium. — Mich, to la. ! and Miss., in meadows and prai- 

 ries. Stem stout, 2 — 3f high. Leaves 3 — 5' (including the 1 — 3" petiole) by 

 3 — b" . Flowers very numerous in each umbel, green, peduncle and pedicels 

 about 1' long. July, Aug. 



3. ENSLENIA. Nutt. 

 In memorj' of Mr. Aloysius Enslen, who collected many plants in the Southern States. 



Calyx small, 5-parted ; cor. 5-parted, segments erect ; corona 5- 

 leaved, leaflets membranaceous, free, truncate, each terminated by 2 

 filiform, flexuous lobes : pollinia oblong, obtuse at base and apex, 

 pendulous ; stig. 5-angled, conical ; follicles cylindraceous, smooth. — 

 % A twining herb, icith opposite., cordate-ovate., acumi?iate lvs. 'fed. ra- 

 cemose-umbellate, mayiy-flowercd. Fls. tohite. 



E. ALBIDA. Nutt. 



Ohio, Clarke 1 to Va. and Ark. Stems slender, with an alternate, pubes- 

 cent line. Leaves thin, glabrous, with rounded, auriculate lobes at base, 2 — 3' 

 diam., margin entire. Peduncles axillary, as long as the petioles. Flowers 

 ochroleucous, sweet-scented. July, Aug. 



4. GO NOLO BUS. Michx. 

 Calyx much smaller than the corolla ; cor. rotate, deeply 5-parted ; 

 corona small, shield form, undulate, 5-lobed ; antheridium depressed, 

 discoid, pentangular, terminated by a membrane ; pollinia transverse, 

 5-pairs ; follicles 2 ; seeds comose. — % St. climbing. Lvs. opposite, cor- 

 date. Pcd. inter pet iolar, raccmcd or corymbose. 



G. MACROPHYLLi'.s. Taud G. hirsutus. Michx. Cynanchium obliquum. 



Jicq. C. macrophyllus. MnJd.) — SI. tomontose-pubesccnt and with sort, 

 .scattered hairs ; lvs. broad, ovate or oval, cordate, acuminate, tomentose-pu- 

 be.*;cent; pv/. sliorter than the petioles, 2 — 5-flowercd, with linear bracts at sum- 

 mit; pet. linear or linear-oblong, obtuse, smooth alcove, minutely puberulent 

 beneaih. — Thickets, along streams, Penn. to Car., W. to Ohio! Ky. Vine 

 trailing or climbing, 3 — fif. Leaves 3 — 5' by 2 — 4', the lobes at base rounded, 

 and often nearly^ or quite closed, with a short acumination at ape.x. Flowers 

 dark purple. Petals 5—7" by 1". June, July. 



5. PERIPLOCA. 



Gr. TTcpt, around, ^Xoncn, a bimliiiK or twiniuK ; 'Vom the hal)it of the i>lnnl. 



Calyx minute ; corolla rotate, flat, 5-partcd, orifice surrounded by 



