ARACE^E. (ARUM FAMILY.) 549 



bryo. A large family, chiefly tropical. Herbage abounding in slender 

 rhaphides. The genuine Araceae have no floral envelopes, and are al- 

 most all monoecious or dioecious ; but the genera of the second section, 

 with more highly developed flowers, are not to be separated. 



* Spathe surrounding or subtending the spadix ; flowers naked, i. e. without perianth. 



1. Arissema. Flowers monoecious or dioecious, covering only the base of the spadix. 



2. Peltandra. Flowers monoecious, covering the spadix ; anthers above, ovaries below. 



3. Calla. Flowers perfect (at least the lower ones), covering the whole of the short spadix. 



Spathe open and spreading. 



* * Spathe surrounding the spadix in n. 4, none or imperfect in the rest ; flowers with a 

 calyx or perianth and perfect, covering the whole spadix. 



4. Symplocarpus. Spadix globular, in a fleshy shell-shaped spathe. Stemlees. 



5. Orontium. Spadix narrow, naked, terminating the terete scape. 



6. Acorus. Spadix cylindrical, borne on the side of a leaf-like scape. 



1. A R I S ^E M A, Martius. INDIAN TURNIP. DRAGON ARUM. 



Spathe convolute below and mostly arched above. Flowers monoecious or 

 by abortion dioecious, covering only the base of the spadix, which is elonga- 

 ted and naked above. Floral envelopes none. Sterile flowers above the fer- 

 tile, each of a cluster of almost sessile 2 - 4-celled anthers, opening by pores 

 or chinks at the top. Fertile flowers consisting each of a 1-celled ovary, tipped 

 with a depressed stigma, and containing 5 or 6 orthotropous ovules erect from 

 the base of the cell ; in fruit a 1 - few-seeded scarlet berry. Embryo in the 

 axis of albumen. Low perennial herbs, with a tuberous rootstock or corm, 

 sending up a simple scape sheathed with the petioles of the simple or compound 

 veiny leaves. (Name from apis, a kind of arum, and afjua, blood, from the spot- 

 ted leaves of some species.) 



1. A. triph^llum, Torr. (INDIAN TURNIP.) Leaves mostly 2, divided 

 into 3 elliptical-ovate pointed leaflets ; spadix mostly dioecious, club-shaped, ob- 

 tuse, much shorter than the spathe, which is flattened and incurved-hooded at 

 the ovate-lanceolate, pointed summit. Rich woods, N. Scotia to Fla., west to 

 Minn, and E. Kan. May. Corm turnip-shaped, wrinkled, farinaceous, with 

 an intensely acrid juice ; spathe with the petioles and sheaths green, or often 

 variegated with dark purple and whitish stripes or spots. 



2. A. Drac6ntium, Schott. (GREEN DRAGON. DRAGON-ROOT.) Leaf 

 usually solitary, pedately divided into 7-11 oblong-lanceolate pointed leaflets; 

 spadix often androgynous, tapering to a long and slender point beyond the oblong 

 and convolute pointed greenish spathe. Low grounds, N. Eng. to Fla., west 

 to Minn., E. Kan., and Tex. June. Corms clustered; petiole 1-2 long, 

 much longer than the peduncle. 



2. PELTANDRA, Raf . ARROW ARUM. 



Spathe elongated, convolute throughout or with a dilated blade above 

 Flowers monoecious, thickly covering the long and tapering spadix through- 

 out (or only its apex naked). Floral envelopes none. Anther-masses sessile, 

 naked, covering all the upper part of the spadix, each of 4-6 pairs of cells 

 imbedded in the margin of a thick and shield-shaped connective, opening by 

 terminal pores. Ovaries at the base of the spadix, each surrounded by 4 - 5 

 distinct, scale-like, white staminodia, 1-celled, bearing 1 -few amphitropous 



