996 LXXX. ASCLEPIADE^. 



(pendulous horizontal or erect) cf these pollen-masEes should be carefully studied, and secondly 

 that the coBfiguration of (he coroua te attended to, for -whilst there is a great general re- 

 semblance in the majority of species belonging to very different genera, the genera themselves 

 are better defined than might have been expected from characters apparently so artificial, — 

 Benth. 



SUBORDEB I. PERIPLOCE^. 



Filaments usually free ; anthers acuminate or with a terminal appendage ; 

 pollen-masses granular, in pairs in each cell. 



Tribe I. Feriploceae. — Characters of the Suborder. 



Corolla-tube cylindrical ; limb spreading. Corona of 5 scales inserted in 

 the tube behind the filaments 1. Gymnaniheba. 



SuBORDEK II. EUASCLEPIADEiE. 

 Filaments connate ; pollen-masses waxy. 



Tribe II. Secamonese. — Anthers with a membranous inflexed tip. Pollen-masses in pairs 

 in each cell (20 in all), sessile in fours (2 pairs) on the corpuscle (the gland on the stigma to which 

 the pollen-masses are attached). 



Corolla rotate ; lobes overlapping to the right . 2. Secamone. 



Tbibe III. Cynancliese. — Anthers with a membranous inflexed tip ; pollen-masses solitary 

 in each cell (10 in all), sessile or pedicellate in pairs on the corpuscle, pendulous. 



Corolla-tube broad often constricted above, the limb spreading or cam- 

 panulate, 5-fid. Corona-scales or segments 5. Stigma umbonate or 



2-rostrate 3. 'ARAnjiA. 



Corolla rotate, broadly campanulate, at length reflexed, 5-fid, valvatc or 



very slightly imbricate. Corona-segments without internal appendages . 4. *Gomphocaepds. 

 Corolla rotate at length reflexed, 5-fid, valvate or very slightly imbricate. 



Corona-segments each with an internal appendage 5. *Asclefias. 



Corolla nearly rotate. Corona membranous, the segments either distinct 

 but not saccate or united in a lobed cup round the gynostegium. 



Corona of 5 segments, quite distinct 6. Vincetoxicdm. 



Corona with 5 or 10 marginal lobes and 5 or 10 additional protruberances 



or lobes inside the margin . . 7. Cynanchcm. 



Corona of S distinct saccate or inflated segments at the back of the 

 anthers, with an exterior corona below them consisting of 5 pro- 

 tuberances or a slightly prominent ring. 



Outer corona very prominent .... 8. Sarcostumma. 



Outer corona scarcely prominent 9. Pentatuopis. 



Tribe IV. DXarsdeniese. — Anthers with a membranous inflexed tip ; pollen-masses solitary 

 in each cell (10 in all), sessile, or pedicellate in pairs on the corpuscle, erect (rarely horizontal or 

 pendulous in Tylophora). 



Corolla-lobes Qverlapping, short. Corona on the corolla-tube 10. Gtmnema. 



Corolla urceolate. Corona-processes minute or none, stigma included . .11. Gonoronema. 



Corolla rotate. Column minute. Corona-processes fleshy 12. Tylophcba. 



Corolla urceolate or salver-shaped. Corona of 5 segments, usually fleshy 



or saccate and adnate at the base with a short erect free or adnate point 13. Marsdenia. 

 Corolla rotate. Corona-segments 5, erect, membranous, peltately attached 



to the back of the anthers 14. Thozetia. 



Corolla rotate. Corona-segments expanding into horizontal spreading 



lamince or disks . . 15. Hoya. 



Corolla urceolate. Corona of 5 linear 2-cleft segments 16. Dischidia. 



Tribe V. Ceropeg'iete. — Anthers incumbent on the stigma, without u membranous tip; 

 pollen-masses 1 in each cell (10 to all), sessile in pairs on the corpuscle, erect or horizontal. 

 Corolla-lobes valvate. 



Corolla rotate. Corona a scarcely conspicuous undulate ring 17. Micbostemma. 



Corolla-tube elongate, lobes oonniveUt at the tips. Corona membranous, 

 cup-shaped, with 5, 10, or 15 lobes . , 18. Cbkopecha, 



