108 ARISTOLOCHIACEAE. 



Family 1. ARISTOLOCHIACEAE Blume. 

 BIRTHWORT FAMILY. 



Acaulescent plants, or with erect or twining stems. Leaves alternate, 

 estipulate. Flowers regular or irregular, sometimes clustered. Calyx- 

 limb 3-6-lobed or irregular. Stamens 6-many, adnate to the pistil ; anthers 

 2-celled, their sacs longitudinally dehiscent. Ovules numerous in each 

 cavity, anatropous, horizontal or pendulous. Fruit a many-seeded 6-celled 

 capsule. Seeds angled or compressed, with a crustaceous testa and usually 

 with a fleshy or dilated raphe ; endosperm fleshy, copious ; embryo minute. 

 Six genera and about 200 species of wide distribution in tropical and tem- 

 perate regions. 



Aristolochia trilofoata L., LOBED-LEAVED DUTCHMAN'S PIPE, BIRTHWORT, 

 West Indian, a vine, several feet long, with petioled deeply 3-lobed leaves 6' 

 long or less, solitary, peduncled, axillary flowers, the lower part of the inflated 

 calyx-limb ovoid, inflated, 6-spurred at the base, about 2' long, the ovate lip 

 tapering into a long tail-like appendage, is commonly planted, climbing on 

 walls and trees, flowering in summer and autumn. 



Aristolochia elegans Masters, ELEGANT DUTCHMAN'S PIPE, Brazilian, oc- 

 casionally planted, is a long slender glabrous vine, with very broadly ovate, 

 cordate, thin leaves 3 '-5' long, the long-stalked drooping flowers with a green- 

 ish tube and a cordate-orbicular limb about 3' broad, which is dark purple and 

 blotched with white. 



Aristolochia argentina Griseb., ARGENTINE DUTCHMAN 's PIPE, of South 

 America, a slender glabrous vine, seen at the Agricultural Station in 1914, has 

 slender-petioled, broadly ovate, cordate, acute leaves about 2' long, and irregu- 

 lar brownish-mottled flowers about V long. 



Order 12. POLYGONALES. 



Herbs, shrubs, trees or vines. Leaves alternate, or sometimes opposite 

 or whorled, the blades mostly entire; stipules mostly present, usually as 

 a sheath (ocrea). Flowers perfect, monoecious, dioecious or polygamous, 

 in variously disposed clusters. Calyx inferior, of 2-6 more or less united 

 sepals sometimes developing keels or wings, often corolloid. Androecium 

 of 2-9 stamens; filaments often dilated at the base; anthers 2-celled, 

 opening longitudinally. Pistil 2-3-carpellary, the ovary superior, 1- 

 celled; styles 2 or 3, more or less united; stigmas capitate or tufted, 

 rarely 2-clef t ; ovule solitary, orthotropous. Fruit a lenticular or 3- 

 angled achene. Seed with horny or mealy endosperm ; embryo with in- 

 cumbent or accumbent cotyledons. Consists of the following family only. 



Family 1. POLYGON ACE AE Lindl. 

 BUCKWHEAT FAMILY. 



Characters of the order. About 40 genera and 800 species, widely dis- 

 tributed. 



