H 



120 POLYGALACE.E. (MILKWORT FAMILY.) 



1. N. aceroides, Moench. (Acer Negundo, L.) Leaflets smoothish 

 when old, very veiny, ovate, pointed, toothed ; fruit smooth, with large rather 

 incurved wings. — River-banks. Pennsylvania to Wisconsin, and southward. 

 April. — A small but handsome tree, with light-green twigs, and very delicate 

 drooping clusters of small greenish flowers, rather earlier than the leaves. 



Order 31. POI<YGAL,ACEJE. (Milkwort Family.) 



Plants with irregular hypogynous flowers, 4-8 diadelphous or monadel- 

 phous stamens, their 1-celled anthers opening at the top by a pore or chink ; 

 the fruit a 2-eelled and 2-seeded pod. — Represented in this country only 

 by the genus 



1. POLlfGALA, Tourn. Milkwort. 



Flower very irregular. Calyx persistent, of 5 sepals, of which 3 (the upper 

 and the 2 lower) are small and often greenish, while the two lateral or inner 

 (called wings) are much larger, and colored like the petals. Petals 3, hypogy- 

 nous, connected with each other and with the stamen-tube, the middle (lower) 

 one keel-shaped and often crested on the back. Stamens 6 or 8 : their filaments 

 united below into a split sheath, or into 2 sets, cohering more or less with the 

 petals, free above: anthers 1-celled, often cup-shaped, opening by a hole or 

 broad chink at the apex. Ovary 2-celled, with a single anatropous ovule pen- 

 dulous in each cell : style prolonged and curved : stigma various. Fruit a 

 small, loculicidal 2-seeded pod, usually rounded and notched at the apex, much 

 flattened contrary to the very narrow partition. Seeds with a caruncle, or va- 

 riously shaped appendage, at the hilum. Embryo large, straight, with flat and 

 broad cotyledons, surrounded by a sparing albumen. — Bitter plants (low herbs 

 in temperate regions), with simple entire often dotted leaves, and no stipules : 

 sometimes (as in the last two species) bearing concealed flowers next the ground, 

 which arc fertilized in the closed bud. (An old name composed of ttoXvs, much, 

 and yaka, milk, from a fancied property of its increasing this secretion.) 



§ 1. Biennials or annuals, ivith alternate leaves, and yellow flowers, which are dis- 

 posed to turn greenish in drying: crest of the keel (lower petal) small: flowering 

 all summer. 



1. P. lutea, L. Low; flowers (bright orange-ydlow) in solitary ovate or oblong 

 heads (%' thick,) terminating the stem or simple branches ; leaves (1'- 2' long) ob- 



' ovate or spatulate ; lobes of the caruncle nearly as long as the seed. — Sandy swamps, 

 New Jersey and southward, near the coast. 



2. P. ramdsa, Ell. Flowers (citron-yelloiv) in numerous short 'and dense spike- 

 like racemes collected in a flat-topped compound cyme; leaves oblong-linear, the 

 lowest spatulate or obovate ; seeds ovoid ; minutely hairy, twice the length of die 

 caruncle. (P. cymosa, Poir., not of Walt. P. corymbosa, Nutt.) — Damp pine- 

 barrens, Delaware and southward. (The allied P. cymOsa, Walt., which is 

 P. graminifolia, Poir., P. attenuata, Nutt. and P. acutifolia, Torr. $c Gray, — 

 known by its simpler cymes, stem naked above, narrower leaves, and globu- 

 lar seeds with no caruncle, — may occur in S. Virginia.) 



