390 LXXXV. ASCLEPIADEZ (BROWN). | Prosopostelma. 
29. PROSOPOSTELMA, Baillon, Hist. P]. x. 247. 
Flowers almost as in Cynanchum. Calyx short. Corolla rotate ; 
lobes narrow, overlapping to the left. Corona of 5 lobes, affixed to 
the bottom of the corolla and opposite to the corolla-lobes, broadly 
petaloid, emarginate and connivent in a cup. Style depressed at the 
apex.—Glabrous twiners. Leaves opposite, cordate. Cymes lateral, 
from one axil, shortly pedunculate.---K. Schum. in Engl. & Prantl, 
Pflanzenfam. iv. ii. 227. ; 
This genus is unknown to me. Baillon states that there are two species natives. 
of W. Tropical Africa, but he does not describe or name them. ‘The position of the 
petaloid coronal-lobes opposite to the corolla-lobes is a very marked character, and 
in this respect it is like Solenostemma, but in allelse it seems to be indistinguishable 
from Cynanchum. Can it be intended for that form of Cynanchum schistoglossum 
in which the corona is divided into 5 cuneately-quadrate lobes alternating with the 
anthers and therefore opposite to the corolla-lobes ? 
30. CYNANCHUM, Linn.; Benth. et Hook. f. Gen. Pl. ii. 762. 
Calyx 5-partite. Corolla very deeply 5-lobed, rotate or rotate-cam- 
panulate; lobes overlapping to the left and straight or more or less 
twisted in bud. Corona arising from the staminal-column near or at 
its base, often membranous, annular, cup-shaped or tubular, toothed 
or lobed at the top or divided nearly or quite to the base into 5 entire 
or toothed lobes, with or without a tooth, lobe, thickening or keels 
within the tube in front of each of the principal teeth or lobes, or on 
the inner face or at the base of the lobes when the corona is divided. 
Staminal-column arising at or near the base of the corolla; filament 
part varying from almost none to a long slender stipe within the 
corona; anther-appendages membranous or slightly fleshy, inflexed 
over the apex of the style or connivent or erect around it. Pollen- 
masses pendulous, solitary in each anther-cell, affixed in pairs by short. 
or long caudicles to the pollen-carriers. Style shorter or longer than 
the anther-appendages; apical part truncate, conical, or rostrate. 
Follicles smooth, winged, or setose. Seeds crowned with a tuft of hairs. 
—Stem twining or erect, leafy, rarely leafless, fleshy. Leaves opposite. 
Flowers rather small, in sessile or pedunculate corymbs, racemes OF 
umbel-like or corymbose cymes, which are subaxillary or lateral 
between the bases of the petioles.— Vincetoricum, Medic. in Act. Acad. 
Theod. Palat. vi. Phys. 404; Moench, Method. Pl. 717; Benth. et 
Hook. f. Gen. Pl. ii. 761. Sarcocyphula, Harv. Thes. Cap. ii. 58. Perian- 
thostelma, Baillon, Hist. Pl. x. 247. _ Schizostephanus, Hochst. ex 
K. Schum. in Engl. Jahrb. xvii. 139. | 
A large cosmopolitan genus. 
I have united Schizostephanus with Cynanchum, as I can find no structural 
difference between them except in the length of the filament-part of the staminal- 
column, which, in Schizostephanus, is very long and slender, and appears to be the 
only character by which it can be distinguished from Cynanchum. A correspond- 
