244 
ARACEAE 
Orchids or Bromeliaceae are such, and it is evident that if this 
method of becoming epiphytic were the only one found in the order, 
these plants could with no more justice be classed as true epiphytes 
than the ivy which may often be seen in the ‘ bowls * of pollard 
willows in Europe (see p. 174), and which has got there by climbing 
up the trunk and dying away below. It is found however that some 
sp. of Philodendron, Pothos &c. are able to commence life as epi- 
phytes. The fleshy fruit is eaten by birds and the seed dropped on a 
lofty branch. The seedling forms clasping roots and dangling aerial 
roots which grow steadily down to the soil, even if it be 100 feet 
or more away. It is hardly possible to suppose that these true 
epiphytic sp. have been evolved in any other way than from former 
climbing sp. The leaves of Philodendron cannifolium Schott have 
swollen petioles full of large intercellular spaces lined with mucilage. 
When rain falls these become filled with water and act as storage 
reservoirs. Lastly, some sp. of Anthurium &c. are true epiphytes 
without any connection with the soil (eg. A . Hiigelii Schott — A. 
Hookeri Kunth.); they have clasping roots, and also absorbent roots 
which ramify amongst the humus collected by the plant itself. The 
aerial roots of some Araceae possess a velamen like that of Orchids. 
[For further details see p. 173, and Schimper’s Epiph. Veg. 
Amerihas.] 
The firs, are without bracts and are usually massed together on a 
cylindrical spadix enclosed in a large spathe; the spadix usually 
terminates a joint of the sympodium (the ‘continuation’ bud is gene- 
rally in the axil of the leaf next but one before the spathe), so that 
there is only one formed each year. Fir. g or monoecious (dioecious 
in Arisaema), with or without a perianth. Sta. typically 6 but 
usually fewer (down to 1), often united into a synandrium (e.g. 
Colocasia, Spathicarpa) ; in Ariopsis the synandria are again united 
to one another. Staminodes are often present, and these also may be 
fused into a synandrodium as in Colocasia. The gynoeceum shows 
almost every possible variety of structure ; it is frequently reduced to 
1 cpl. Fruit a berry. The outer integument of the seed is often 
fleshy. Endosperm or none. 
The firs, are usually protogynous (even when monoecious). In 
many genera (incl. most in Eur.) the smell is disagreeable and 
attracts carrion flies as pollen carriers (see Arum, Dracunculus, 
Helicodiceros &c.). 
Many A. contain latex, which is usually poisonous but is dis- 
pelled by heat. The rhizomes of many sp. contain much starch and 
are used as food (Caladium, Colocasia, Arum &c.). 
Classification and chief genera (after Engler): 
The grouping of the A. is very difficult and account has to be taken 
of histological as well as external characters. 
I. POTHOIDEAE (land pits.; no latex or raphides; leaves 
