Class 2. DICOTYLEDONS. 
Vascular bundles open and arranged + in circles. 
Venation reticulate. Embryo (almost always) with 
2 cotyledons. Radicle prolonged (at least at first) 
into a tap-root. Flow, predominantly 4 — 5-merous. 
Sub-Class L ARCHICHLAMYDE.E (cf. 
P- 35 )- 
Per. double, single or o. Cor. when present, poly- 
petalous (exc. in Cotyledon), but the pet. may be 
frequently suppressed. 
§ I. Amentiflorce (Moss) (cf. p. 14). 
Mostly trees or shrubs. Lea. generally deciduous. 
Flow, often i-sexual ; generally, and 9 often, in 
catkins; each flow, mostly with bract and 2 brac- 
teoles. Per. sepaloid or o. Endosperm o (exc. in 
CANNABACE^ and URTICACE^). 
SALICALES . JUGLAND ALES . URTICALES . 
MYRICALES. FAGALES. 
Order i. SALICALES. 
Trees or shrubs. Lea. spiral, simple, stipulate 
(but stipules frequently deciduous). Flow, in cat- 
kins, dioecious. Per. (or disc) cup-shaped or o. Sta. 
2 — oo- Carp. (2), with 2 styles; ovary i-celled; plac. 
parietal ; ovules 00, anatropous. Fr. a loculicidal 
capsule. Seeds with a basal tuft of hairs. 
Family 19. SALICACEiE. Characters of the 
order. Salix, Populus. 
II 
