378 NATURAL HISTORY OF PLANTS. 



ovulate ovary cells, rarely co -ovulate. Embryo exalbuminous. Leaves 

 alternate (rarely opposite), often compound pinnate. — 40 genera. 



4. PANCOViEiE. — Polygamo-dioecious irregular flowers. Petals fewer 

 in number (4) than the sepals (5). Irregular, incomplete, unilateral 

 disk exterior to the androceum. Gyna'ceum excentric, with 1-2- 

 ovulate ovary cells, rarely co-ovulate. Embryo exalbuminous. 

 Leaves alternate, generally compound-pinnate. — 22 genera. 



5. -^scuLEiE. — Flowers irregular, polygamo-diojcious. Petals the 

 same or fewer in number (4) than the sepals, joined more or less 

 high. Gynajceum slightly excentric. Ovary cells 2-ovulate. Fruit 

 capsular. Seeds cxarillate. Embryo exalbuminous, conferruminate. 

 Leaves opposite, compound-digitate. — 2 genera. 



6. MELiANTHEiE. — Flowcrs irregular, polygamo-dicecious. Andro- 

 ceum uTegular, exterior to the disk. Ovules co. Fruit capsular or 

 vesicular. Seeds albuminous, with or Avithout aril. Embryo straight. 

 Leaves alternate, pinnate, provided with stipules. — 3 genera. 



7. AiTONiE^. — Flowers regular, 4-merous. Calyx gamosepalous. 

 Stamens monadelphous, exterior to a cupula-shaped disk. Fruit 

 capsular, vesicular. Cells 1-2-spermous. Seeds exalbuminous. 

 Embryo bent. Leaves simple, alternate, or fasciculate. Flowers 

 axillary. — 1 genus. 



8. AcEEEiE. — Flowers regular, polygamous or dia3cious. Calyx 

 and corolla isomerous (or apotalous flowers). Stamens more or less 

 interior with reference to the circular disk, regular or equally lobate. 

 Ovary with 1-2-ovulate cells. Fruit dry, with indehiscent cells 

 (usually samaroid). Seeds destitute of aril and albumen. Leaves 

 simple or compound-pinnate, opposite. — 2 genera. 



The variable characters employed to distinguish the series arc 

 then principally : the situation of the leaves, alternate or opposite, 

 simple or compound, and, in the latter case, pinnate or digitate ; the 

 regularity or ii-rcgularity of the flowers, the petals being equal 

 to the sepals or else four in number, and the place of one of them 

 remaiuiug unoccupied, while the calyx is pentamerous ; the regu- 

 larity or irregularity of the disk surrounding the gyneeceum or only 

 occupying one of its sides ; its position, relatively to the stamens to 

 which it is generally exterior, while, more rarely, its elements are 

 interposed to them or even become interior to the androceum, that is 

 to say, placed close against tlie foot of the gyuiBceum ; the situation 

 of this which is cither central or excentric ; the organisation of the 



