122 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 
Plants generally less than 3 dm. high. 
Hypanthium cupulate ; petals spatulate-oblong. 11. H. cuneata. 
Hypanthium saucer-shaped; petals broadly obovate. 12. H. platypetala. 
$3. CAPITATAE. 
In general habit resembling the preceding group, but the imflorescence more con- 
tracted, fastigiately corymbose-cymose or subcapitate. Hypanthium deeply cup-shaped ; 
bractlets linear. Filaments of the outer stamens much broader than those of the inner 
ones, broadly triangular. Pistils numerous. Petals, except in Nos. 13 and 19, obcordate, 
unguiculate, white, or often tinged with rose. 
Leaflets merely toothed (except sometimes in the first species). 
Plants less than 2 dm. high; cyme fastigate-corymbose ; pubescence dense. 
Pubescence densely silky-canescent. 13. H. Hendersoni. 
Pubescence densely glandular puberulent. 14. H. parviflora. 
Plants generally over 2 dm. high. 
Pubescence of both leaves and stem more or less villous. 15. H. pseudocapitata. 
Pubescence rather scant, on the leaves scarcely any, on the upper part of the stem glandular. 
Leaflets obovate or oval, 2-3 cm. long ; bracts generally exceeding the inflorescence. 
16. H. capitata. 
Leaflets obovate or cuneate, .75-2 em. long ; bracts shorter than the inflorescence. 
17. H. fusca. 
Leaflets divided more than half way to the midvein into linear or linear-oblong segments. 
Stem glandular above; petals cuneate, emarginate. 18. H. tenella. 
Stem hirsute-villous, not glandular ; petals oblong. 19. HH. tenwiloba. 
$4. TRIDENTATAE. 
Stems slender and ascending ; leaves pinnate with 2-4 pairs of cuneate leaflets, which 
are 2-3- (seldom 5-) toothed at the apex. Hypanthium cupulate or campanulate. 
Petals oblanceolate or spatulate, unguiculate, white or yellowish. Stamens 10; fila- 
ments often linear-lanceolate. Pistils few, 5-15. 
The group approaches Jvesia in several characters, viz., the narrow filaments, few 
pistils and the form of the petals. It is, however very nearly related to the following 
one, with which H. congesta connects it; in that species the lower stipules are occasion- 
ally pinnately dissected. 
Petals white, oblanceolate ; filaments linear-lanceolate ; cyme rather fastigiate. 20. H. tridentata, 
Petals yellowish, at least in dry specimens. 
Cyme subcapitate ; outer filaments triangular to lanceolate. 21. H. flavescens. 
Cyme few-flowered and open; filaments all linear-lanceolate. 22. H. congesta. 
