Part 1, 1922 AMBROSIACEAE 25 
I. Montanae. Herbs, mostly annuals, with pinnatifid or bipinnatifid leaves; heads 
numerous in leafy panicles; staminate involucre mostly 6-lobed, with 3 dark ribs, one in each 
of the 3 upper lobes; paleae filiform with slightly clavate tips or rudimentary; anthers with 
cuspidate incurved tips; fruit small, glandular-puberulent or slightly pubescent, 1-celled, 
usually 1-flowered; beak solitary, one lobe much longer than the other; spines flattened or 
channeled, not hooked. ; 
1. Franseria acanthicarpa (Hook.) Coville, Contr. U. S. Nat. 
Herb. 4: 129. 1893. 
Ambrosia acanthicarpa Hook. Fl. Bor. Am. 1: 309. 1833. 
Franseria Hookeriana Nutt. Trans. Am. Phil. Soc. II. 7: 345. 1840. 
Gaertneria Hookeriana Kuntze, Rev. Gen. 339. 1891. 
Gaertneria acanthicarpa Britton, Mem. Torrey Club 5: 332. 1894. 
An annual herb, or perhaps sometimes perennial; stem 3-6 dm. high, branched, striate, 
strigose as well as more or less hirsute, with scattered white hairs with pustulate bases; leaves 
petioled, bipinnatifid almost to the midrib, strigose on both sides and somewhat hirsute on 
the veins; blades ovate in outline, 5-10 cm. long; divisions linear to oblong, from rounded to 
acute at the apex; heads numerous in leafy panicles, the staminate ones racemose, on peduncles 
. 3-4 mm. long; involucre 2.5—4 mm. broad, sparingly hispidulous or glabrate, dark olive-green, 
with 3 dark ribs in the upper lobes; lobes ovate, rounded at the apex; corolla glabrous; pistil- 
late heads in small clusters in the upper axils, 1-flowered; fruit 8-10 mm. long, ellipsoid, spar- 
ingly hirsute or glabrate, slightly glandular-granuliferous, reticulate-ridged; beak solitary, 
subulate; spines flattened, 8-20, in 3-4 series, lanceolate, connected with ridges, about 4 mm. 
long. 
The northern form is more hispid than the southern, and with larger, permanently hairy 
fruit. 
TYPE LOALITY: Banks of the Saskatchewan. 
DISTRIBUTION: Sandy soil, Saskatchewan and Alberta to Missouri, Texas, and southern Cal- 
ifornia. 
ILLUSTRATIONS: Britt. & Brown Ill. Fl. f. 3595; ed. 2, f.4229. 
2. Franseria montana Nutt. Trans. Am. Phil. Soc. II .7: 345. 
1840. 
An annual herb, or perhaps scmetimes perennial; stem 3-6 dm. high, branched, striate and 
somewhat strigose; leaves petioled, pinnately parted or lobed, strigose on both sides; blades 
ovate in outline, 2-7 cm. long; divisions fobed or toothed, obovate or the terminal one ovate, 
the upper confluent; lobes and teeth of the lower leaves usually rounded at the apex; heads 
numerous in leafy panicles, the staminate ones racemose, on peduncles 3—4 mm. long; involucre 
4-6 mm. broad, sparingly hispidulous, with three dark ribs running into the three upper lobes, 
sometimes with an additional but fainter one in the innermost lobe; lobes rounded, ovate; corolla 
glabrous; pistillate heads in clusters in the upper axils, 1-flowered; fruit about 8 mm. long, 
slightly glandular-puberulent; beak subulate, 3 mm. long; spines 15-30, in about 4 series, 
flattened, channeled, lanceolate or linear-lanceolate or rarely rudimentary in some of the 
heads. 
TYPE LOCALITY: Rocky Mountains, near the Colorado of the West. 
DISTRIBUTION: Oregon to Wyoming, Utah, and California. 
3. Franseria Palmeri Rydberg, sp. nov. 
An annual herb; stem 5-7 dm. high, branched, striate, glandular-granuliferous and his- 
pidulous; leaves petioled, pinnately parted or lobed, strigose; blades ovate or deltoid in out- 
line, 3-5 cm. long; divisions obovate or the terminal one rhombic; secondary lobes oblong and 
rounded at the apex; heads numerous in leafy panicles, the staminate ones racemose, 
on peduncles 2-3 mm. long; involucre 5-6 mm. in diameter, sparingly hispidulous, with 3 
dark ribs; lobes usually 6, rounded; corolla glabrous; pistillate heads in small clusters, 1-flow- 
ered; fruit about 8 mm. long, sparingly villous when young; beak subulate, 3 mm. long; spines 
10-18, in 2-3 series, flattened and channeled, linear-lanceolate. 
