Euphorbia 



EUPHOEBIACE^ 



335 



minute scale at the joint. Stamen one, the short filament jointed 

 with the pedicel. Bracteoles within the involucre linear or 

 setaceous, sometimes partly united. Female flower one in the 

 centre of the involucre, pedicel at length lengthened beyond the 

 involucre. Perianth none or of three minute scales. Ovary sessile 

 at the top of the pedicel, 3-celled ; styles three, distinct or more 

 or less united, spreading above, entire or divided into two ; ovules 

 solitary. Capsule breaking up from the persistent axis into three 

 2-valved cocci ; endocarp horny. Seeds without a caruncle in 

 Jamaican species (present in the naturalized E. Peplus), with 

 endosperm ; cotyledons flat, broad. 



Species about 1000, very widely dispersed in the temperate 

 regions, fewer within the tropics. 



A. Glands of the involucre with a petaloid appendage.* 

 Leaves all opposite, shortly petioled, usually oblique 

 at the base. Herbs or shrubs. 

 Shrubby, or perennial herbs. 

 Leaves pointed to blunt, base auriculate-cordate 1. E.buxifolia. 



Leaves with rounded or emarginate apex 2. E. myrtillifolia. 



Annual weeds. 



Upright-growing. Involucres cymose. 

 Branches, involucre, capsule hairy. 



Capsule minutely puberulous with adpressed 



hairs; seeds pinkish. Appendage minute 3. E. hirta. 

 Capsule densely puberulous; seeds brownish 



red to ash colour. Appendage evident 4. E. lasiocarpa. 

 Branches, involucre, capsule glabrous. 

 Cymes terminal with slender branches. 

 Leaves oblong or obovate, more or less 

 serrulate. 



Stipules ciliate 5. E. brasiliensis. 



Stipules glandular-dotted on margin... 6. E. nirurioides. 



Leaves almost ligulate, mostly entire 7. E. hyssopifolia. 



Cymes axillary. Leaves irregularly ellip- 

 tical, serrulate 8. E. hypericifolia. 



Prostrate. Involucres mostly solitary, glabrous 

 (sometimes puberulous in E. thymifolia) . 

 Stem puberulous along one side only. Cap- 

 sule hirtellous along the keeled edges, 



pendent 9. E. prostrata. 



Stem puberulous to glabrate. Capsule puber- 

 ulous, younger erect 10. E. thymifolia. 



Stem and capsule glabrous 11. E. Blodgettii. 



. Leaves alternate, but opposite or ternate at ends of 

 branches. Herbs with hollow jointed stems, 



constricted at the joints 12. E. Oerstediana. 



Leaves ternate or whorled, sometimes opposite. 



Shrubs with jointed branches 13. E. nudiflora. 



* Appendage minute in E. hirta, sometimes wanting in E. prostrata 

 and E. thymifolia. 



