8 KEY TO FAMILIES. 



Flowers perfect, rarely polygamous, in racemes or spikes. 



[nflorescence with a Bpathe; calyx 4-lobed; stamens 4..Araceae, p. 87. 

 [nflorescence naked; calyx of 6 distinct sepals, or none; stamens 6 or 1. 



JUNCAGINACEAE, p. 31. 



2. Flowers ix the axils ok dry chappy bracts, arranged in spikes or 



spikelets. 



Steins mostly terete and hollow; leaves in 2 rows; sheaths mostly split open 

 opposite the Made; bract lets 2 to each tlower; tin it a grain (seed adnate 



t.» the pericarp) Gramineae, p. 34. 



Stems mostly triangular, solid; Leaves in 3 rows; sheaths entire; Ligule obsolete 

 or minnte; bract let 1 to each flower; fruit an achene (seed free from the 

 pericarp) Cyperaceae, p. 80. 



B. Perianth always present, its segments in 2 series, often corolla-like; 



parts of the flower usually equal in number; carpels united 



into one compound ovary. 



Ovaries several, distinct, becoming achenes; perianth of 3 sepals and 3 petals. 



Alismaceae, p. 32. 

 Ovary 1 and 



Superior; perianth regular; stamens 6, sometimes :'■ or 4. 



Perianth-segments distinct, green or brown, not petal-like; rush-like plants. 



.1 [JNCACEAE, p. 89. 



Perianth-segments distinct or partly united, at least the inner petal-like; 



plants not rush-like LiLiACEAE, }). 92. 



Inferior. 



Perianth regular; stamens 3 Iridaceae, p. 110. 



Perianth irregular; stamens 1, rarely 2 Orchidaceae, p. 112. 



CLASS 2.— DICOTS. 



Leaves netted-veined; parts of the flower mostly in 4s or 5s; vascular bundles 

 in a ring around a central pith, the stem when perennial increasing in girth 



by annual layers; embryo with 2 cotyledons. 

 I. APETALOUS DIVISION. Corolla none; calyx present, herbaceous or 

 sometimes petal-like, sometimes none. 



A. Flowers monoecious or dioecious, one or both kinds in catkins; 



trees or shrubs. 



1. Leaves pinnately compound. 



Leaves alternate; only the staminate flowers in catkins; fruit a nut with a 



fibrous coat FUGLANDACEAE, p. 120. 



2. Leaves simple. 



Leaves opposite; (lower dioecious, 1 to 3 in each axil of the connate bracts. 



Garryaceae, p. 304. 

 Leaves alternate. 



Bol li kinds of flowers in catkins. 



Flowers I t<> each scale or bract; perianth none. 



IVnit a 1 celled many seeded capsule; seeds with a coma; flowers dioe- 



cious; foliage deciduous Salicaceae, p. 117. 



f'rnit a wn\y coated berry; flowers monoecious or dioecious; foliage 



evergreen Myricaceae, p. L20. 



