ARACE.E. (ARUM FAMILY.) 
445 
Class II. MONOCOTYLEDONOUS or ENDOGENOUS 
PLANTS. 
Stems with no manifest distinction into bark, wood, and 
pith ; but the woody fibre and vessels collected into bundles 
or threads which are irregularly imbedded in the cellular 
tissue: perennial trunks destitute of annual layers. Leaves 
mostly parallel-veined (nerved) and sheathing at the base, 
seldom separating by an articulation, almost always alter¬ 
nate or scattered and not toothed. Parts of the flower com¬ 
monly in threes. Embryo with a single cotyledon (or if 
two they are alternate). 
Order 109. ARACEiE. (Arum Family.) 
Plants with acrid or pungent juice, simple or compound 
often veiny leaves, and monoecious or perfect flowers crowd¬ 
ed on a spadix, which is usually surrounded by a spathe. 
Floral envelopes none, or of 4 - 6 sepals. Fruit usually a 
berry. Seeds with fleshy albumen, or none but filled with 
the large fleshy embryo in Nos. 2, 4, and 5. 
Synopsis. 
* Spadix surrounded by a spathe. 
1. Arum. Flowers monoecious or polygamo-dioecious, naked,cov- 
ering the base only of the spadix. 
2. Peltandra. Flowers monoecious, naked, covering the whole 
spadix : spathe long and convolute. 
3. Calla. Flowers perfect, naked (no floral envelopes), covering 
the spadix : spathe open and spreading. 
4. Symplocarpus. Flowers perfect, with a calyx of 4 hooded se¬ 
pals, covering the oval spadix, all combined in fruit. 
* * Spadix naked (without a spathe). Sepals 4-6. 
’ rontium * Spadix terminating a naked scape. 
corus. Spadix bursting from the side of a leaf-like scape. 
38 * 
