438 THE STORY OF PLANT LIFE 



Family 4. Polygalaceae (Vol. II, p. 139). — Flowers 

 zygomorphic, 5-partite ; sepals 5, 2 larger, petaloid, winged ; 

 petals 3 ; stamens 8, united into a tube below ; ovary 

 syncarpous, 2-locular ; ovule i in each loculus, on axile 

 placenta ; style i ; fruit a capsule. 



Genus, Poly gala (Vol. II, p. 141). 

 Sub-Order 3. Tricocc^. — Flowers actinomorphic, often 

 reduced ; carpels 3 ; seed with caruncle. 



Family 5. Euphorbiaceae (Vol. Ill, p. 233). — 

 Flowers apetalous ; inflorescence compound, cymose, 

 ultimate branches cyathia, in involucre of 5 fused bracts ; 

 male flowers many, of i stamen; female flowers solitary, 

 terminal, 3-locular ; styles 3 ; fruit a capsule splitting into 3 

 mericarps. 



Sub-Family. Crotonoidese. 

 Tribe i. Acalyphece. 



Genus. Mercurialis (Vol. Ill, p. 242). 

 Tribe 2. Euphorbiece. 



Genus. Euphorbia (Vol. Ill, p. 237). 

 Sub-Order 4. Callitrichine^.. 



Family 6. Callitrichaceae. — Plant monoecious; 

 flowers naked, with 2 sickle-shaped bracteoles; male flower 

 of I terminal stamen ; female of 2 carpels ; fruit a drupe- 

 like mericarp. 



Genus. Callitriche (Vol. II, p. 237). 



Order 15. Sapindales. — Like Gerianales, but 

 ovules in the reverse position, pendulous with dorsal 

 raphe and micropyle facing upv^ards, or ascending 

 with ventral raphe and micropyle facing downwards. 



Sub-Order i. Buxine^e. — Flowers haplochlamydeous ; 

 ovules with 2 integuments. 



Family i. Buxacese, —Flowers regular; stamens 4 to 



