Part 4, 1924] 



POLYGALACEAE 



307 



Capsule subquadrate or broadly cuneate-quadrate, little broader 

 than long, slightly lobed or merely emarginate, with erect 

 or ascending lobes. 

 Capsule usually subquadrate, 11 mm. wide or less. 



Leaves ovate-lanceolate to oval, or when obovate not 

 abruptly short-pointed at apex. 

 Leaves 0.6-2.8 (rarely 5) cm. long; petioles 1-2.5 

 mm. long. 

 Leaves obovate or oval, 6-19 mm. long, usually 



with fascicles of smaller ones in their axils. 6. P. guantattatnat 



Leaves ovate to elliptic or oval, 1.5-2.8 (rarely 5) 



cm. long, without axillary fascicles. 7. P. oblongata. 



Leaves 3.5-8.5 cm. long; petioles 3-9 mm. long. 8. P. ja?naicensis. 



Leaves broadly obovate or oval, abruptly short -pointed 



at apex. 9. P. stipitata. 



Capsule broadly cuneate. 12-13.5 mm. wide; leaves broadly 



oval, rounded and usually emarginate at apex. 10. P. montana. 



Capsule transversely oblong, much broader than long, deeply 



lobed, with spreading or divergent lobes. 1 1 . P. propinqua. 



Peduncle longer than the pedicels; racemes loosely flowered. 12. P. Fuertesii. 



III. MlCROTHRIX 

 Leaves nearly uniform, oval or ovate. 



Plant densely pubescent with spreading hairs. 



Capsule merely ciliate; wings shorter than keel. 13. P. ovatifolia. 



Capsule puberulous on the sides; wings longer than keel. 14. P. buxifolia. 



Plant puberulous with incurved or appressed hairs. 



Wings subpersistent. 15. P. myrtilloides. 



Wings deciduous. 



Leaves oval or elliptic, obtuse or rounded. 



Flowers 3.8 mm. long. 16. P. Robinsonii. 



Flowers 5.3-5.8 mm. long. 17. P. Xanti. 



Leaves ovate, acuminate. 18. 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. 19. P. Pavoni. 



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

 pubescent on the sides. 

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

 scarious margin less than the height of the corneous umbo. 

 Hairs of stem all incurved or appressed. 

 Capsule more or less pubescent on sides. 

 Flowers 4-5 mm. long. 



Aril sessile, higher than long. 20. P. Magdalenae. 



Aril subpedicellate by the pointed base of seed, 



longer than high. " 21. P. piliophora. 



Flowers 6-7 mm. long. 



Stems hirsute-tomentose above. 22. P. leptosperma. 



Stems barely puberulous above. 44. P. oaxacana. 



Capsule merely ciliate at maturity. 



Middle and upper leaves strongly reduced, 5-14 mm. 

 long, linear or lance-linear. 

 Aril with more or less distinct dorsal lobe, sub- 

 pedicellate by the pointed base of seed. 23. P. Barbeyana. 

 Aril without distinct dorsal lobe, subsessile. 



Aril with subglabrous umbo. 24. P. zacatecana. 



Aril with densely pilose umbo. 25. P. intricata. 



Middle and upper leaves not reduced, 15-31 mm. 

 long. 

 Middle and upper leaves obovate-oblong, 4.5-7 



mm, wide. 26. P. Palmeri. 



Middle and upper leaves linear, 1.5-3 mm. wide. 27. P. racemosa. 

 Hairs of stem (at least in part) wide-spreading. 



Hairs of stem all short and wide-spreading; leaves not 



reticulate. 28. P. rectipilis. 



Hairs of stem partly long and spreading, partly short 

 and incurved; leaves reticulate. 

 Middle and upper leaves linear or linear-lanceolate, 



1.8-4 mm. wide. 36. P. retifolia. 



Middle and upper leaves oblong-lanceolate or oval, 



4.5-16 mm. wide. 37. P. atnphothrix. 



Aril larger, the depth of the lobed or lobulate scarious margin 

 equaling or exceeding the height of the corneous umbo. 

 Capsule merely ciliate at maturity; aril not veil-like. 

 Upper leaves linear to narrowly lanceolate. 



Stems incurved-puberulous, rarely nearly or quite 

 glabrous. 

 Upper leaves strongly reduced, 5-14 (-23) mm. 



long. 29. P. reducta. 



