Part 1, 1922 AMBROSIACEAE 29 
hirsutulous and glandular-puberulent, reticulate, ridged and pitted, 1-flowered; beak solitary, 
conic; spines somewhat broadened below, hooked at the apex. 
Type collected at Jimulco, Coahuila, May 17, 1885, Pringle 192 (N. Y. Bot. Gard.). 
DISTRIBUTION: Coahuila to Aguascalientes and San Luis Potosi. 
13. Franseria tenuifolia* Harv. & Gray; A. Gray, Mem. Am. Acad. 
4: 80. 1849. 
Ambrosia longistylis? A. Gray, Men. Am. Acad. 4: 79. 1849. Not A. longistylis Nutt. 1840. 
Franseria tenuifolia tripinnatifida A. Gray, Bost. Jour. Nat. Hist. 6: 227. 1850. 
Xanthidium tenuifolium Delpino, Studi. Lign. Anem. 62. 1871. 
Gaertneria tenuifolia Kuntze, Rev. Gen. 339. 1891. 
A perennial herb; stem 3-6 dm. high, more or less hirsute with white spreading hairs; 
leaves interruptedly bi- or tripinnatifid, coarsely strigose on both sides and hirsute on the 
veins beneath, 1—-1.5 dm. long; blades ovate in outline; segments of the lower leaves oblong or 
oval, obtuse or rounded at the apex, the terminal one short;, segments of the upper leaves 
narrower, usually linear and acute, and the terminal one often elongate; inflorescence a leafy 
panicle but branches rather few; staminate heads many, on peduncles about 2 mm. long, 
nodding; involucre 3-4 mm. broad, turbinate-saucer-shaped, hispidulous and glandular- 
puberulent; lobes about 10, triangular; paleae of the receptacle filiform with slightly spatulate 
tips; corolla puberulent; pistillate heads in small clusters in the upper axils, 1-flowered, sub- 
tended by oval bract-like leaves; fruit hirsute and glandular-puberulent, reticulate, about 
3 cm. long; beak solitary, conic; spines about 15 in 2—3 series, short, broadened at the base 
and hooked at the apex. 
TYPE LOCALITY: Pofii Creek, between Bent’s Fort [Colorado] and Santa Fé [New Mexico]. 
DISTRIBUTION: Texas to California & Coahuila. 
14. Franseria caudata Rydberg, sp. nov. 
A perennial herb; stem 3—4 dm. high, sparingly white-hispid with ascending hairs; leaves 
subsessile, 5-15 cm. long, interruptedly bipinnatifid, strigose on both sides; segments linear- 
lanceolate, divergent and often falcate, the terminal ones often elongate; inflorescence a rather 
simple raceme; staminate heads very short-peduncled; involucre saucer-shaped, about 5 mm. 
broad, glandular-puberulent and sparingly hispidulous; lobes about 8, rounded-ovate; paleae 
of the receptacle nearly filiform, slightly clavate; pistillate heads in small clusters in the upper 
axils and at the base of the staminate raceme, 1-flowered; fruit fully 4 mm. long, glandular- 
puberulent and slightly hispidulous, strongly pitted; beak solitary, conic, 1 mm. long; spines 
15-18 in 2-3 series, somewhat broadened below, hooked at the apex, connected by rounded 
ridges. 
Type collected near Gray, Lincoln County, New Mexico, September 1, 1898, Josephine Skehan 
108 (N. Y. Bot. Gard.). 
DISTRIBUTION: Western Texas and New Mexico. 
15. Franseria hispidissima Rydberg, sp. nov. 
A perennial herb; stem more than 5 dm. high, strongly angled, hispid as well as glandular- 
puberulent; leaves tripinnatifid, hispid, subsessile; blades ovate in outline, 3-7 cm. long; seg- 
ments narrowly linear; staminate heads very numerous in leafy panicles; involucre about 3 mm. 
wide, saucer-shaped, hispidulous and glandular-puberulent; lobes 6-8, broadly triangular, 
often apiculate; paleae of the receptacle filiform; corolla brownish on the margins and angles, 
puberulent; pistillate heads in the upper axils, 1-flowered; fruit about 3 mm. long, hispidulous 
and glandular-puberulent, with pits above the spines; beak solitary, conic; spines 8-12, in 2 
series, conic, slightly broadened below, hooked at the apex. 
Type collected at Real de Pifios, Zacatecas, Leon Diquet (N. Y. Bot. Gard.). 
*Gray (Syn. Fl. ed. 2. 12: 449. 1886) gives as a synonym Ambrosia tenuifolia Gren. & Godr. 
Fl. Fr. 2: 395. 1852; but Grenier & Godron’s description applies to A. tenuifolia Spreng., and 
Cosson’s plant, mentioned by Gray, belongs to the same. 
