STANDLEY TEEES AND SHRUBS OF MEXICO. 579 



1. POLYGALA L. Sp. PI. 701. 1753. 



Herbs, shrubs, or trees, with alternate estipulate leaves and racemose flowers; 

 sepals free or the two lower united ; wings petaloid ; keel crested, beaked, or 

 unappendaged ; stamens 8 or rarely 6 ; fruit a 2-celled 2-seeded thin-walled 

 capsule; seeds usually pubescent and arillate. 



The species are of little economic importance but some are used in medicine, 

 diaphoretic, expectorant, and emetic properties being ascribed to them. Others 

 are used locally as remedies for snake bites, and some are said to have poison- 

 ous properties. 



Keel blunt, without crest or beak. 

 Sepals all free. 

 Sepals and wings at least in part deciduous. 



Sepals all herbaceous, deciduous like the wings, or with them rarely 

 subpersistent ; aril pubescent at least at apex. 

 Capsule and leaves not obviously glandular. 



Leaves small, mostly 6 to 20 mm. long, usually distinctly dimor- 

 phous, the lower shorter, oval or oblong-oval, the upper oblong 

 to linear or rarely uniform, but then smaller than in the next 



group I. MICROTHRIX. 



Leaves comparatively large, mostly 2 to 6 cm. long, 1 to 3 cm. wide, 

 ovate, gradually reduced upward, not noticeably dimorphous. 



II. HEBANTHA. 



Capsule and leaves bearing large glands III. ADENOPHORA. 



Sepals not all herbaceous, the lower ones petaloid, deciduous like the 

 wings, the upper one herbaceous, persistent; aril glabrous. 



IV. BILOBA. 



Sepals and wings persistent, the sepals herbaceous V. HTJATECA. 



Sepals not all fr^e, the two lower ones connate. Wings and sepals persistent. 



VI. HEBECLADA. 

 Keel with a beak or crest. 

 Keel with a conic or cylindric beak, not crested. 



Sepals (except usually the upper) and wings deciduous. 



VII. ETJRHINOTROPIS. 



Sepals and wings persistent VIII. PANTOMONE. 



Keel with a fimbriate crest IX. MONNTNOPSIS. 



I. MICROTHRIX. 



Leaves nearly uniform, oval or ovate. 

 Plant densely pubescent with spreading hairs. 



Capsule merely ciliate; wings shorter than keel 1. P. ovatifolia. 



Capsule puberulous on the sides ; wings longer thau keel 2. P. buxif olia. 



Plant puberulous with incurved or appressed hairs. 



Wings subpersistent 3. P. myrtilloides. 



Wings deciduous. 



Leaves oval or elliptic, obtuse or rounded 4. P. xanti. 



Leaves ovate, acuminate 5. P. serpens. 



Leaves more or less dimorphous, the lower oval or oblong, the upper longer, 

 linear to oblong, elliptic, or ovate. 



Wings glabrous; capsule merely ciliate 6. P. pavoni. 



Wings pubescent, at least at base, or if rarely glabrous, then capsule pubes- 

 cent on the sides. 

 Aril small, the depth of the entire or merely denticulate-lobulate scarious 

 margin less than the height of the corneous umbo. 



