1907] Hall. Compositae of Southern California, 237 



minating in spines, the inner inocuous. Receptacle soft-bristly 

 or hairy, not fleshy. Corollas tubular, their segments linear- 

 filiform. Achenes compressed or 4-angled, smooth in all our 

 species. Pappus a single series of bristles connate at the very 

 base and deciduous as a whole. 



The subgenus Cirsium, which includes all the native Ameri- 

 can thistles, is distinguished from Eucarduus only by the plumose 

 pappus-bristles of all but the marginal achenes. Yet some bot- 

 anists would receive it as a distinct genus. 



Leaves moderately if at all decurrent. 



Heads sessile or short-pedunculate, bracteose-leafy at base. 



Involucral bracts entire, the innermost often with scarious tips. 

 Corolla-lobes with callous capitate tips: bracts of the involucre 



not appressed-imbricate, narrow 1. C. edulis. 



Corolla-lobes acute: bracts of the involucre appressed-imbricate, 



the short outermost ones ovate 2. C. Drummondii. 



Involucral bracts finely spinescent on the margins above the middle 

 3. C. maritimus. 



Heads solitary on long peduncles, not bracteose-leafy at base. 



Flowers red or crimson, the corolla-lobes longer than the throat 



4. C. occidentalis. 



Flowers white or cream-color to pink, the corolla-lobes equalling or 



shorter than the throat 5. C. Californicus. 



Leaves strongly decurrent, the middle cauline ones for one-third their length : 

 desert species 6. C. Mohavensis. 



1. C. edulis (Nutt.) Greene, Proc. Phila. Acad. for 1892, 362 

 (1893). Cirsium edule Nutt., Trans. Am. Philos. Soc. ser. 2, vii. 

 420 (1841). Cnicus edulis Gray, Proc. Am. Acad. x. 47 (1874). 



Stem simple, robust but tender and succulent, 2 or 3 dm. high ; 

 pubescent and leafy up to the terminal cluster of nearly or quite 

 sessile heads: leaves narrowly oblanceolate or oblong, sinuate- 

 pinnatifid, very prickly-ciliate but the prickles weak, the upper 

 surface green, more or less white-tomentose beneath: heads de- 

 pressed-globose : involucre 2.5 to 3 cm. high, conspicuously 

 arachnoid-woolly when young; bracts gradually tapering from a 

 narrow base to a weak prickle or soft point, not very unequal: 

 flowers dull purple or whitish, segments of the corolla shorter 

 than the throat and callous-thickened at apex. 



Rare at Pasadena and San Bernardino ; near the sea-coast not 

 far from Santa Maria, Santa Barbara Co., Miss Eastwood, no. 



