246 
ARACEAE 
2 -ranked or spiral ; lateral veins of 2nd and 3rd order netted; 
firs, usually 5): Pothos, Anthurium, Acorus. 
II. MONSTEROIDEAE (land pits.; no latex; raphides; lat. 
veins of 3rd, 4th, and sometimes 2nd orders netted ; fir. $ , 
usually naked ; ovule anatrop. or amphitrop.) : Rhaphido- 
phora, Monstera, Spathiphyllum. 
III. CALLOIDEAE (land or marsh pits.; latex ; fir. usually $ ; 
ovule anatrop. or orthotrop.; If. never sagittate, usually 
net-veined): Symplocarpus, Calla. 
IV. LASIOIDEAE (land or marsh pits.; latex; fir. $ or $ $ ; 
ovule anatrop.; seed usually exalbum.; If. sagittate, often 
much lobed, net-veined): Dracontium, Amorphophallus. 
V. PHILODENDROIDEAE (land or marsh pits.; latex; fir. 
naked, unisex.; ovule anatrop. or orthotrop.; seed usually 
album.; If. usually || -veined): Philodendron, Zantedeschia. 
VI. CO LO CASIO IDE A E (land or marsh pits. ; latex ; fir. naked 
unisex.; sta. in synandria; ovule orthotrop. or anatrop.; 
seed album, or not; If. net- veined) : Remusatia, Colocasia. 
VII. AROIDEAE (land or marsh pits.; latex; fir. unisex., 
usually naked ; sta. free or in synandria ; ovule anatrop. 
or orthotrop. ; seed album. ; leaves various, net-veined ; 
stems mostly tuberous) : Spathicarpa, Arum, Dracunculus, 
Helicodiceros, Arisaema. 
VIII. PISTIOIDEAE (swimming pits.; no latex; fir. unisex., 
naked; S firs, in a whorl, ? solitary): Pistia (only genus). 
Engler gives a genealogical tree of these groups, showing also 
their relation to Lemnaceae, thus 
Monsteroideae 
j f Calloideae ->■ Philodendroideae. 
Pothoideae J Lasioideae. 
[ Aroideae -»• Pistioideae LEMNACEAE. 
1 
Colocasioideae. 
For further details of this most interesting order, see the account 
in Nat. PJi . (by Engler), from which much of the above is abridged. 
[Placed in Spadiciflorae (Eichl. Warm.), Nudiflorae (B. & H.).] 
Arachis Linn. Leguminosae (in. 7). 7 sp. Braz. A. hypogaea L. is 
the earth-, ground-, or pea-nut, largely cultivated in warm regions for 
its seeds, which are edible and which when pressed yield one of the 
many oils used in place of, or to adulterate, olive oil. The fir. 
after fertilisation bends downwards (cf. Linaria) and the elongation 
of its stalk forces the young pod under ground, where it ripens. 
Aralia Tourn. Araliaceae. 30 sp. N. Hemisph. The root of A . 
Ginseng Baill. (A. quinquefolia auct.) is the source of the famous 
Chinese medicine Ginseng. It is much valued in China as a tonic 
