270 NORTH AMERICAN FLORA 
Petals cuneate, truncate or emarginate; outer stamens much 
broader than the inner. 
Leaflets densely crowded and imbricate ; 
cymose. 
Leaves of 2-4 pairs of leaflets, which are 2-3- (seldom 5-) toothed only 
at the apex or entire. 
Lower stipules dissected into linear-filiform hairy segments. 
inflorescence open, 
I, CALIFORNICAE. 
Bractlets usually 3-toothed ; stem stout. 
Basal leaves with 34 pairs of leaflets; fruiting calyx 5-6 mm. in diam- 
[VOLUME 22 
IV, CApITATAE. 
V. SERICATAE. 
VI, TRIDENTATAE, 
VII. HIRSUTAE. 
eter. 1. H. frondosa. 
Basal leaves with 4-10 pairs of leaflets; fruiting calyx about 1 em. in di- 
ameter. 2. A. californica. 
Bractlets usually entire. 
Stem slender; basal leaves with 15-25 leaflets. 3. AZ, elata. 
Stem stout ; basal leaves with about 11 leaflets, 4. H. glandulosa. 
II, CUNEATAE. 
Leaflets flabelliform, dissected. 
Hypanthium and calyx 5-6 mm. long ; sepals lanceolate. 5. H. Michenerz. 
Hypanthium and calyx about 3 mm. long; ; Sepals ovate. 6. H. Wilderae. 
Leatiets merely toothed. 
Pubescence dense, silky, not at all glandular, except slightly so on the 
branches of the inflorescence and the hypanthium i in A. Clevelandi. 
Piant densely canescent. . A. Rydbergii. 
Plant green or greenish. 
Pubescence very short and dense. 
Plant stout, 3-6 dm. high; leaflets thick, obovate, 10-25mm.long. 8. H. Kelloggii. 
Plant slender, 2-4 dm. high ; leaflets obovate-cuneate to reni- 
form, 5-10 mm. long. 9. H. Clevelandi, 
Pubescence longer and less dense ; plants 2-4 dm. high. 
Pubescence appressed; hypanthium cupulate. 10. A. bernardina, 
Pubescence spreading ; hypanthium nearly saucer-shaped. ll. H. Bolanderi. 
Pubescence more or less hirsute and glandular, 
Plants usually over 3 dm. high ; petals spatulate or oblong. 
Flowers 15-20 mm. in diameter ; hypanthium saucer-shaped ; 
pedicels often 2.5 cm. long. 
Leaflets acute, regularly and coarsely toothed. 12. H. platycalyx. 
Leaflets truncate, finely toothed and with usually 3 large teeth 
at the apex. 
Flowers about 10 mm. in diameter; hypanthium cupulate ; pedi- 
cels 0.5-1.5 cm. long 
Plants usually less than 5 dm. high. 
Hypanthium cupulate ; petals spatulate- oblohg. 
Hypanthium saticer-shaped ; petals broadly obovate. 
III. TENUILOBAE. 
Leaflets thick, densely pubescent, cleft about half their length or less ; 
plant 1-2 dm. high. 
Leaflets Piae spanaely hairy, cleft into linear lobes to near the base ; plant 
34 dm. h 
IV. CAPITATAE. 
Plant less than 3 dm. high ; petals 2-3 mm. long. 
Leaflets cleft with lanceolate or oblong divisions ; 
Leaves densely hairy. : 
Leaves sparingly hairy or glabrate. 
Leaflets obovate, toothed with rounded teeth, densely glandular-pubern- 
inflorescence open. 
lent ; inflorescence dense. 21. 
Plant usually over 3. dm. high ; petals 3-6 mm. long. 
Leaflets merely toothed. 
Pubescence of both leaves and stem more or less villous. 22. 
Pubéscence rather scant, on the leaves scarcely any, on the upper 
part of the stem glandular, 
Leaflets ovate or oval, 2-3 cm. long; bracts generally exceeding 
the inflorescence. 
Leaflets obovate or cuneate, usually less than 2 em, long ; bracts 
shorter than the inflorescence. 
Leaflets divided more than halfway to the midrib into linear or linear- 
oblong divisions. 
V. SERICATAE, 
Plant silvery with long appressed hairs, 
Plant hispidulous and glandular-puberulent. 
15, 
16, 
19. 
20. 
26. 
27. 
13. A. truncata. 
14. A. puberula, 
FT. cuneata. 
HI. Parryt. 
7. H. Hendersonii. 
18. 
AT, tenutloba, 
AT, Brownii. 
AT, tenella. 
HI. parviflora, 
HI, pseudocapitata. 
23. H. capitata, 
24. AY, fusca. 
25. A. tenutsecta. 
AI, sericata, 
AT, hispidula, 
