ARACE^. 625 



Order 210. — AEACEiE, the Arum Family. (Mono-Hypog.) Flowers 

 generally unisexual, rarely Msexual, enclosed within a spathe, and 

 usually on a spadix (fig. 260, p. 178), having male flowers at its 

 upper part, female below, and abortive flowers between them (flg. 

 260, 2, p. 178). Perianth either 0, or in the 5 flowers rudimentary 

 and scaly. Stamens definite or 00, hypogynous ; anthers extrorse. 

 Ovary free, 1-3- or more celled ; ovules solitary or numerous ; style short 

 or ; stigma simple. Fruit succulent or dry, indehiscent, one-celled, 

 very rarely three-celled ; seeds one or several ; embryo in the axis of 

 fleshy or mealy albumen, sometimes with a lateral cleft for the 

 plumule; radicle usually next the hilum. — Herbaceous or shrubby 

 plants, often with tubers or creeping rhizomes, leaves sheathing at the 

 base, and having parallel or branching veins (fig. 260, 1, p. 178). 

 They occur in dry and marshy places, and in lakes in various parts of 

 the world, abounding in the tropics. The order has been divided 

 into four sub-orders : — 1. Arinese, Cuckoo-pint tribe (fig. 260) ; 

 naked flowers with a spadix and spathe, J ?, anthers sessile, ovules 

 several, fruit succulent, seeds pulpy. 2. Typhinese, Bulrush-tribe; 

 marsh or ditch plants, with nodeless stems, flowers J ?, with a scaly 

 or hairy perianth, arranged on a spadix, without a spathe, anthers 

 wedgeTshaped on long filaments, ovule solitary, fruit dry, seed with 

 adherent pericarp. 3. Acorese, Sweet-flag tribe; flowers $, having 

 usually a scaly perianth, arranged on a spathaceous spadix, ovules 1 or 

 more, fruit a berry. 4. Pistiese, or Lemnese, Duckweed tribe ; flowers 

 5 5, naked, enclosed in a spathe without a spadix, ovary 1-celled, ovules 

 2 or more, fruit membranous or capsular. The order includes 60 

 genera and 286 species. Examples — -Arum, Caladium, Colocasia, 

 CaUa; Typha, Sparganium; Acorus, Orontium, Pothos; Pistia, 

 Lemna. 



The general property of the order is acridity. Sometimes the 

 plants are dangerous irritant poisons. In some instances the rhizomes 

 yield much starchy matter, and when boiled or roasted are used as 

 substitutes for yams, under the name of Coco. The starch may be 

 separated and used as Arrow-root. Thus, Portland Sago is prepared 

 from the rhizome of Arum maculatum, common Cuckoo-pint, or 

 Wake-Eobin. Dieffenlachia seguina (Galadium segwinum) is called 

 Dumb-cane, on account of the swelling of the tongue caused by 

 chewing the plant. Many of the plants of this order give out heat in 

 a marked degree during flowering (p. 259). Some send out aerial 

 roots, by means of which they climb upon trees. Monstera (Tonielia) 

 deliciosa has perforated leaves (p. 81) ; it yields an edible fruit. Sijm- 

 plocarpus fxtidus, Skunk-cabbage, has a very disagreeable odour. Its 

 rhizome and seeds have been used as antispasmodics. Bichardia 

 africana, with ,its white spathe, is commonly cultivated under the 

 name of Ethiopian Lily. The root-stock oi Acorus Calamus, Sweet- 



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