142 KEY AND FLORA 



49. OXALIDACEJE. WOOD SORREL FAMILY 



Herbs or woody plants. Leaves compound. Flowers in fives, 

 bisexual, actinomorphic, hypogynous. Stamens 10, somewhat 

 monadelphous at the base. Ovary with several ovules in each 

 cell. Fruit a capsule. 



OXALIS L. 



Acid herbs. Leaves basal or alternate, with or without 

 stipules, usually of 3 leaflets, which droop at night. Sepals 5. 

 Petals 5. Stamens 10. Ovary 5-lobed, 5-celled ; styles 5. 



1. 0. Acetosella L. WOOD SORREL. Apparently stemless, from a 

 creeping, scaly rootstock. Leaves all basal, long-petioled, of 3 in- 

 versely heart-shaped leaflets ; scape slender, 2-5 in. high, 1-flowered. 

 Flowers nearly 1 in. in diameter, white, veined with red or purple. 

 Cold woods N. 



2. 0. violacea L. VIOLET WOOD SORREL. Perennial from a 

 bulbous root, apparently stemless. Leaves long-petioled ; leaflets 

 inversely heart-shaped, sometimes slightly downy, often with a dark 

 zone near the middle. Scapes usually longer than the petioles, uin- 

 bellately 4-10-flowered; pedicels slender. Flowers violet-purple, nod- 

 ding. Petals obtuse, 2-3 times as long as the sepals; scapes and 

 petioles 4-5 in. long. Common in rich woods.* 



3. 0. corniculata L. COMMON YELLOW WOOD SORREL. Probably 

 flowering the first year but perennial, propagated by slender whitish 

 rootstocks. Erect or decumbent, often sparsely hairy, usually 1 ft. 

 or less in height. Stem leafy, the leaves often appearing whorled. 

 Leaflets thin, green or purplish, often ciliate. Peduncles few-flowered, 

 the ascending pedicels, clad with spreading hairs, forming unsym- 

 metrical umbels or cymes at their summits. Flowers yellow, about 

 ^ in. in diameter. Pods hairy, columnar, grooved, often ^ in. or more 

 in length. A common weed in light soil. 



50. TROP^OLACEJE. INDIAN CRESS FAMILY 



- Smooth and tender herbaceous plants, with biting juice, often 

 climbing by the petioles of their simple leaves. Leaves alter- 

 nate, without stipules. Peduncles axillary, 1-flowered. Sepals 

 3-5, the upper one with a long, distinct spur. Petals 1-5, 

 hypogynous, not always all alike. Stamens 6-10, perigynous, 



