152 COMPOSITAE 
pitoe yeas beneath ; — simple or branched below, the pistillate heads at their base and clus 
red in the upper axils; staminate heads about 3-5 mm. thick, 16-30-flowere ~ the in woluere 
t 
int eel and Cae 6-10-toothed; fruit turbinate-subglobose, abou mm. lon ered, 
2-3-beaked, the body densely lanate-tomentose, thickly covered with numero rigid fe a 
grooved, mostly uncinate-tipped spines 3-5 mm. long, the lower mostly seeks lecclale and flat- 
tened, the upper subulate, s apeerets: 
r Son uthwestern San Diego County, California, and Lower California. Type 
lodaiting: Y masbalecn Bay, Lower: Chtien April-May. 
7. Franseria ambrosioides Cav. Ambrosia-leaved Burbush. Fig. 5226. 
Franseria brosioides Cav. Ic. 2: 79. 1793. 
Gaertner brosioides Kuntze, Rev. Gen. Pl. 1: 339. 1891. 
Suffrutescent perennial, 1-2 m. high, the ascending stems several from the base, leafy, mostly 
unbranched below the inflorescence, a andinioe. puberulent and grayish-hirsute. Le: ves 6-18 cm. 
long with petioles 1-4 cm. long. elongate-triangular to Gnckakie acuminate, cordate to broadly 
co y toot i i i 
—2 1-2- ed, tie be sa ew vise 
lon ng, spines many, spreading, slender, slightly flattened, pe nice 5 athe Seek hooked at the 
Sted ert slopes and sandy washes, Lower Sonoran Zon ear San Diego, San Diego County, California (where 
it pro gale was introduced), south to Lower California and tine southern Arizona south to Sinaloa and Durango. 
Type locality: Mexico. Fe .-May 
8. Franseria ilicifolia A. Gray. Holly-leaved Burbush. Fig. 5227. 
veer tierfong te 10 Proc. Amer, eo i fst 1876. 
Kuntze, Rev. Gen. Pl. 1: 3 
staminate racemes = ut 8 cm. long, the pistillate heads at their base and mostly solitary in the 
upper axils; staminate heads 7-10 mm. wi ah Rs ut 60-flowered, the involucres considerably ex- 
ceeding the "flow wers, ea about 14 lance-ova r lanceolate, spinescent- shine phyllaries, connate 
pas their length or less, the sorte Sapliate ~glandular ; fruit fusifo orm 0  gltbtes fasilor , 1-2.3 
long, 1-2-beaked, usually 2-flowered, seine stipitate- “glandular, heatiee below the beaks 
aden rigid, oiekae ShcHeee-tisned ‘flat ish or grooved spines 4-6 mm. long. 
Desert washes and canyons, Lower Sonoran vie Riverside and Imperial Counties, rnia, to northern 
a i eee estern Arizona, Type locality : Great Canyon of the antes as riers ec Moun- 
ains, 
25. XANTHIUM L. Sp. Pl. 987. 1753. 
arse monoecious annuals with branching stems. Leaves alternate, petiolate, netiate 
to nearly entire, or lobed. Staminate heads borne above the pistillate; in lucres 1 
flowered, the phyllaries free in 1-3 series; receptacle cylindric, paleaceous. Pistillate in- 
i ate i 
Achenes linear or sometimes ovate, — Me se. [From the Greek word meaning 
up ee ancient name of some plant producing a dye that color. 
cally unstable genus of uncertain origin with pie Me about 3 species. Many species have been 
aie bey = “garviktion of the bur. Type species, Xanthium strumarium L. 
Spines lacking in the leaf-axils; leaves deltoid-ovate to subtriangulate, long-petioled. 1. X. strumarium. 
Conspicuous 3-forked spines at axils of leaves; leaves lanceolate, short-petioled. 2. X. spinosum. 
1. Xanthium strumarium L. Cocklebur. Fig. 5228. 
Xanthium strumarium L. Sp. Pl. 987. 1753. 
Erect, ae Sed branching annual 2.5-8 dm. high with stout, striate, scabridulous stems. Leaf- 
blades 6-12 cm ong and usually equally as wide, the petioles as og a or longer, deltoid-ovate or 
- so 
: m 
margin dentate or serrate, scabrid above and below;; pistillate pectneces crowded, 1-3 in leaf-axils 
or on gabe par aed: sa burs about 1-1.5c¢ m. Tong, ellipsoid or fusiform, as ale brown to green- 
e puberulence, the pric ie ee up to 2 mm. gre straight except for the hooked 
ope slabrous os and puberulent and glandular at be the beaks stouter, about the length of 
the prickles, straight o: acura 
4 ena areas; Soa in the Pacific States only from the Colorado Desert, California (Cameron Lake, Bran- 
degee; Fort Yuma, Pe arish), but widespread in the American tropics and in Europe. Type locality: not known. 
