46 KEY TO PLANTS. 
Stigma sessile, 3-8-lobed. Leaves alter- 
nate. Perianth 3-4-partite, imbricate. 
Stamens (both filaments and anthers) 
connate in a column. Ovary 3-4-celled. 
Tropics of the Old World. 
Nepenthaceae. 
(4) Leaves bearing no pitchers. Flowers her- 
maphrodite, rarely trees with unisexual 
or polygamous flowers. Style usually 
present, more rarely stigma sessile, 
entire or bilobed. ‘Et 
77 (a) Stamens perigynous. Leaves opposite or 
verticillate, exstipulate. Perianth-lobes 
valvate in bud. Lythrarveae. 
(4) Stamens hypogynous. Leaves alternate 
rarely almost opposite or verticillate. 
78 
78 (a) Stamens 1-4 or 6. Perianth of 4 distinet 
leaves, imbricatein bud. Ovary 2-celled 
very rarely 3-4-celled. Seeds exal- 
buminous. Herbs, rarely undershrubs. 
Leaves exstipulate. Ovules parietal. 
Cruciferae. 
(0) Stamens 5, 8, or more. Perianth valvate 
in bud, or 5-10-lobed and imbricate. 
Ovary 3-20-celled. Seeds albuminous. 
Trees or shrubs, rarely undershrubs. 79. 
