426 aracejE. (abum family.) 



Class II. MONO COT YLEDONOUS or EN- 

 DOGENOUS 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 tis- 

 sue : 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 (and the 

 leaves of the plumule alternate). 



Oeder 112. ARACE^, (Arum Family.) 



Plants with acrid or pungent Juice, simple or compound often veiny leaves, 

 and monoecious or perfect flowers crowded on a spadix, which is usually sur- 

 rounded by a spaihe. — 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. (A large family, chiefly tropical.) 



Synopsis. 



* Spadix surrounded by a spathe. 

 H- Flowers naked, i e destitute of any floral envelopes. 



1. ARIS^MA. Flowers monoecious or dioecious, coTering only the base of the spadix. Spathe 



convolute below. 



2. PBLTANDRA. Flowers moncecious, covering the whole surface of the spadix ; the anthers 



above, the ovaries below. 



5. CALLA. Flowers perfect (at least the lower ones), covering the whole surface of the short 



spadix. Spathe open and spreading. 



■*- -t- Flowers with a regular calyx. 



4 SYMPLOCARPUS. Flowers perfect, covering the whole of the oval spadix, each with a 



calyx of 4 hooded sepals, all combined into one mass in fruit. 

 * * Spadix naked (not surrounded by any spathe) Flowers perfect and with a calyx. 



5 ORONTITJM Spadix terminating a naked scape Stamens 4-6 : anthers 2-celled. 



6. ACORUS. Spadix bursting from the side of a leaf-like scape. Stamens 6 : anthers 1-celled- 



1. AKISyEBIA, Martius. Indian Tuenip. Dkagon-Akum. 



Spathe convolute below and mostly arched above. Flowers by abortion dioe- 

 cious, or moncecious, covering the base of the spadix, which is elongated and 

 naked above. Floral envelopes none. Sterile flowers above the fertile, consist- 

 ing of whorls of 4 or more stamens, with very short filaments and 2 - 4-ceUed 



