Part 1, 1922] AMBROSIACEAE 
bo 
N 
the segments; secondary segments lanceolate or ovate, often 1 cm. long, toothed; staminate 
heads in a terminal raceme; involucre saucer-shaped, 5-6 mm. broad, hirsute as well as glan- 
dular-puberulent; lobes 8-10, rounded-ovate; paleae of the receptacle filiform, slightly clavate 
and pubescent towards the apex, sometimes tinged with purple; corolla pubescent; pistillate 
heads in small clusters in the upper axils and at the base of the staminate raceme, 1-flowered; 
fruit about 1 cm. long, slightly villous and glandular-puberulent; beak single, elongate-conic, 
3 mm. long; spines 15-20, in about 4 series, linear-lanceolate in outline, deeply channeled, 3 
mm. long. 
TypPE LocaLiry: California. i ‘ : 
DISTRIBUTION: Washington to southern California, along the coast. 
7. Franseria Chamissonis Less. Linnaea 6: 507. 1831. 
Franseria Chamissonis malvaefolia Less. Linnaea 6: 507. 1831. 
Franseria cuneifolia Nutt. Trans. Am. Phil. Soc. II. 7: 345. 1840. 
Franseria Chamissonis cuneifolia T. & G. Fl. N. Am. 2: 293. 1842. 
Gaertneria Chamissonis Kuntze, Rev. Gen. 339. 1891. 
Ambrosia Chamissonis Greene, Man. Bay Region 188. 1894. 
A perennial herb, with a creeping rootstock; stem decumbent at the base, hirsute, striate, 
2-4 dm. high; leaves simple, petioled, densely silky-strigose; blades oblanceolate, elliptic, 
spatulate, or cuneate, acute or rounded at the apex, cuneate at the entire base, coarsely crenate 
or dentate to incisely-lobed, 2-5 cm. long; staminate heads in a dense terminal spike, subsessile: 
involucre saucer-shaped, 7-8 mm. wide, somewhat hirsute; lobes 8-10, semi-orbicular or round- 
ed-ovate; paleae of the receptacle filiform, with slightly spatulate tips; corolla with brown 
angles and margins; pistillate heads in small axillary clusters and at the base of the stamin- 
ate spike, 1-flowered; fruit about 1 cm. long, hirsute; beak solitary, conic, short; spines 25— 
30, inabout 4 series, dilated, not hooked, narrowly lanceolate and boat-shaped, ciliate, their bases 
connected by low ridges. 
Type LocaLity: California. 
DISTRIBUTION: Vancouver Island to California. 
(?) Franseria Chamissonis < Lessingii. Franseria Chamissonis viscida Eastw. Proc. Calif. 
Acad. III. 1: 117. 1898. Gaertneria Chamissonis viscida A. Heller, Muhenbergia 1: 6. 1900. 
Like F. Chamissonis but the leaves more or less cleft or the lower even pinnatifid; more coarsely 
hairy than F. bipinnatifida X Chamissonis. San Nicolas and San Clemente Islands, California. 
III. Tenuifoliae. Annual or perennial herbs with branched roots, or shrubby, at least 
below; leaves bi- or tri-pinnatifid, strigose or hirsute; heads numerous in leafy panicles; stam- 
inate involucre with 8—13 round lobes; paleae mostly filiform with dilated tips; anthers with 
acuminate incurved tips; fruit very small, reticulate-rugose; beak solitary, the lobes unequal; 
spines short, hooked at the apex. 
8. Franseria linearis Rydberg 
Gaertneria linearis Rydb. Bull. Torrey Club 32: 133. 1905. 
A low perennial, shrubby at the base; stems about 3 dm. high, sparingly hirsute, angled 
and striate; leaves subsessile, once or twice pinnatifid, 3-4 cm. long, strigose above, minutely 
tomentulose beneath, ovate in outline; divisions linear, obtuse, 3-5 mm. long, somewhat 
revolute-margined; heads racemose, the staminate ones nodding, on peduncles 1-2 mm. Ieng; 
involucre saucer-shaped, green, strigose, 3-4 mm. wide: lobes about 8, rounded-ovate; paleae 
of che receptacle spatulate, 1-nerved; corolla glabrous; pistillate heads few, in the upper axils, 
1-flowered; fruit strigose; beak subulate; spines 12-15, in about 3 series, nearly terete, hooked 
at the apex. 
TYPE LocaLiIty: Calhan, Colorado. 
DISTRIBUTION: Known only from the type locality. 
9. Franseria canescens (Benth.) Rydberg 
Ambrosia frulicosa var. Benth. Pl. Hartw. 17. 1839. 
Ambrosia fruticosa canescens Benth.; Hemsl. Biol. Centr. Am. Bot. 2: 150. 1881. 
Ambrosia canescens A. Gray, Proc. Am. Acad. 17: 217. 1882. 
A perennial herb, with a rootstock; stem 3-5 dm. high, sparingly strigulose or glabrate; 
leaves short-petioled, tripinnatifid, densely white-strigulose on both sides or merely grayish 
