Twentieth, twenty-first class. 
43 
— Stem with more than 2 Is, or in any case the Is not 
opposite. . . . .14 
14. Stem 1—2 fid. Lip inflated, sabot-shaped 
Cypripedium. 564. 
— FIs in a spike or a many-fld raceme ... 15 
15. Lip not jointed. Ls net-veined . . Goodyera. 559. 
•— Lip with 2 joints ....... 10 
16. Ovary twisted, sessile . . . Cephalanthera. 555. 
— Ovary pedicelled, pedicel twisted . . Epipactis. 556. 
Cl. 21. Moncecia. 
1. Ligneous pis (trees or shrubs) . ... 2 
— - Water pis (submerged or floating) . . . 17 
— Herbaceous pis, growing on land or in swamps . 24 
— Grass-like pis.Carex. 609. 
2. Resinous trees, gen. with acicular, persistent ls 3 
— Trees, the ls more or less broad, gen. falling in the 
autumn ......... 3 
3. Ls small, at any rate partly scale-like . . 4 
— Ls narrow, linear (acicular) ..... 5 
4. Fr.-scales united at last and forming a false berry 
Juniperus. 669. 
— Fr.-scales leathery-scarious or ligneous, forming a cone 
4& 
4a. Scales of the cone imbricate (overlapping one another). 
Twigs flattened.Thuia. 671. 
— Scales of the cone shield-shaped. Twigs 4-cornered 
Cupressus. 670. 
5. Scales of the cone thickened at the top, with a shield 
Pinus. 672. 
— Scales of the cone thinner at the top . Abies. 673. 
6(2). Ls pinnate. Walnut .... Juglans. 513. 
— Ls simple, lobed, or pinnatiBd .... 7 
7. Male and fem. fls, or at any rate the males, in catkins 
8 
— Fls not in catkins ....... 15 
8. Male and fem. fls in catkins . .... 9 
— Fem. fls not in catkins ...... 12 
9. Fem. catkins in racemes of 3—5 (on a common peduncle). 
Alder ....... Alnus. 521. 
— Fem. catkins solitary ...... 10 
10. Anthers glabr. at the top. Fem. catkins dense. Birch 
Betuia. 520. 
I . 
— Anthers with tufts of hair at the top. Fem. catkins lax 
11 
