ASTERACEAE. 379 



uncled, their Involucres broadly hemispheric, open, 5-12- 

 lobed; receptacle chaffy; corolla regular, with short 

 tube and 5-lobed limb; anthers scarcely coherent, 

 mucronate- tipped . 



Spines of the involucre hooked. 1. G. tenuifolia. 

 Spines of the involucre straight. 



Annual; inland species. 2, G. acanthicarpa. 



Perennial; maritime species. 3. G. hipinnatifida. 



1. G. tenuifolia (Gray) Kuntze. Perennial, erect, 4-15 dm. 

 high, leafy throughout, hispid or varying to glabrate; leaves mostly 

 2-3-pinnately parted or dissected into narrow oblong or linear lobes, 

 the narrow rachis often with a few interposed small lobes, the ter- 

 minal elongated; staminate racemes elongated and paniculate; 

 pistillate heads in numerous glomerules below, in fruit minutely 

 glandular, about 2 mm. long, armed with 6-18 short and stout 

 incurving spines, their tips usually hooked and with an excavated 

 cartilaginously bordered areola about each. (Franseria te?tuifolia 

 Gray.) 



Rather common about Cahuenga Pass. 



2. G. acanthicarpa (Hook.) Britton. Annual, diffuse, hirsute or 

 hispid; the stems and branches 3-10 dm. long; leaves ovate or 

 roundish in outline, 2.5-7 cm. broad, bipinnatifid; sterile racemes 

 numerous, short; fruiting involucre 6-8 mm. high, with fiat lanceo- 

 late-subulate spines. (Franseria aca^ithicarpa Hook.) 



Common on the dry plains of the interior valleys. July- Sep- 

 tember. 



3. G. hipinnatifida (Nutt.) Kuntze. Perennial, procumbent; 

 stems 6-10 dm. long, hirsute; leaves ovate in outline, 2.5-5 cm. long, 

 2-3-pinnately parted, with oblong lobes, canescent with soft tomen- 

 tum or finely hirsute; staminate spikes or racemes dense; fruiting 

 involucre ovate-fusiform, 6-8 mm. long, armed with rather short 

 and thick flattish spines, their acute tips somewhat incurved. 

 {Franseria hipinnatifida Nutt.) 



Common along the seashore on beach sands and on the sand- 

 dunes. Flowering nearly throughout the year. 



29. XANTHIUM L. Cockle-bur. 

 Monoecious annual branching coarse rough or spiny 

 herbs, with alternate lobed or dentate leaves, and rather 

 small heads of greenish flowers, the staminate ones capi- 

 tate-clustered at the ends of the branches, the pistillate 

 axillary. Involucre of the staminate heads with short 

 distinct bracts in 1-3 series; receptacle chaffy; corolla 

 tubular, 5-toothed; anthers not coherent, mucronate at 

 apex; filaments united. Involucre of pistillate heads 

 ovoid or oblong, closed, covered with hooked spines, 

 1-2-beaked, 2-celled, each cell containing 1 ovoid or ob- 

 long achene; corolla none; pappus none. 



