138 CL, AROIDEZ (BROWN). 
Stem rarely woody. Leaves alternate, radical or cauline, usually with 
sheathing petioles, net- or parallel-veined. Spathe open to the base or 
the lower part convolute or tubular, wholly deciduous or persistent, or 
only the tubular part persistent. 
A large order, of about 100 genera, and about 1000 species, chiefly concentrated 
in the tropics of both hemispheres, very few in temperate regions. 
“Flowers unisexual. 
tPeriauth none, 
Female part of spadix adnate to the back of the 
spathe ; flowers unilateral. 
Female flower or ovary solitary ; a floating herb 1. PISTIA. 
Female flowers or ovaries 3-12... 3 . 17. CALLOPSIS. 
Female part of spadix free from the spathe, 
bearing flowers all round. 
{Spadix with a terminal appendix destitute of 
flowers, but sometimes covered with filiform 
processes or hairs ; herbs with a tuberous 
rootstock, 
Leaves and flowers produced together (see 
also Amorphophallus angolensis). 
Leaves peltate, cordate- or sagittate- 
ovate ; spadix moncecious ; ovary 
i-celled ; ovules numerous on 
parietal placentas . - 
Leaves 3-partite, pedate, or with 
several leaflets radiating from the 
apex of the petiole; spadix often 
unisexual ; ovary l-celled; ovules 
8. COLOCASIA. 
basal, orthotropous . ‘ . 38. ARISEMA. 
Leaves and flowers produced at different 
times. 
Leaves pedate ; margins of the spathe 
connate into a tube below ; spadix 
with neuter organs above the 
female flowers . < - 2. SAUROMATUM. 
Leaves 3-branched at the apex of the 
petiole; branches dichotomously 
divided, pinnatipartite; spathe con- 
volute below, except in.4, Elliotii ; 
spadix without neuter organs . 4. AMORPHOPHALLUS. 
{{Spadix without a terminal appendix. 
§Herbs with a tuberous rootstock or a thick 
fleshy rhizome ; no distinct stem. (See 
also Anubias, which has a creeping 
rhizome.) 
Spadix with barren organs (staminodes) 
on the apical part. 
Ovary 2-celled ; ovule solitary in each 
cell ; anthers connate in pairs . 5. ZYGANTHERA. 
Ovary 1-celled ; anthers connate in 
groups of 4-8 . s . 10. TypHONODORUM. 
Spadix with barren organs (staminodes ?) 
between the ovaries and fertile an- 
thers, none on the apical part ; ovary 
