1907] Hall. Compositae of Southern California. 101 



1. P. camphorata (L.) DC., Prodr. v. 452 (1836). Erigeron 

 camphoratus L., Sp. PI. ed. 2, 1212 (1763). SALT-MARSH FLEA- 

 BANE. 



An erect annual, branching above, 3 to 8 dm. high (some- 

 times even 4 or 5 m. high, when growing near saline springs in 

 the desert): herbage soft-puberulent, glandular above: leaves 

 oblong-ovate or lanceolate, acute at each end, glandular-dentate, 

 short-petioled or the upper sessile, the larger 7 to 14 cm. long 

 and 2 or 3 cm. wide: involucral bracts chartaceous, ovate- 

 lanceolate, commonly reddish : central hermaphrodite flowers 

 varying from 10 or 12 to numerous : achenes pubescent : pappus- 

 bristles all slender, not at all dilated above. 



In moist, saline soil from San Diego Co., Santa Catalina 

 Island, and the Colorado Desert (Dos Palmas, etc.), north; also 

 in Arizona and Texas and along the Atlantic seaboard ; especial- 

 ly common in salt-marshes near the coast. 



2. P. sericea (Nutt.) Coville, Contr. U. S. Nat. Herb. iv. 128 

 (1893). Polypappus sericeus Nutt., PI. Gamb. 178 (1848). 

 Tessaria borealis Gray, PL Wright, i. 102 (1852). Pluchea 

 borealis Gray, Proc. Am. Acad. xvii. 212 (1882). ARROW-WEED. 



Slender willow-like shrub 2 to 5 m. high (or in depauperate 

 plants much smaller) : herbage silvery-silky throughout except 

 on the old stems: leaves alternate, entire, linear-lanceolate, 1 to 

 3.6 cm. long, 3 to 6 mm. wide, acute at apex, tapering to the 

 sessile base : outer involucral bracts brown or purplish, firm- 

 coriaceous, the white inner ones much thinner : style-branches of 

 the pistillate flowers slender, long-exserted at maturity: central 

 hermaphrodite flowers 20 or less, their pappus-bristles slightly 

 dilated at tip. 



Fairly common west of the mountains from the northern 

 boundary of Santa Barbara Co. (Cuyama River) and Santa 

 Catalina Island to San Diego ; very common in suitable localities 

 on the Colorado Desert ; less common on the Mohave Desert 

 (Death Valley, ace. to Coville; Needles; etc.); east to the Eio 

 Grande. A specimen gathered by Dr. Davidson on Wilsons 

 Peak illustrates the effect of unfavorable environment, being 

 nearly simple and only 45 cm. high, but the flowers of the four 

 well developed heads are perfectly normal. 



