210 University of California Publications in Botany. [ VoL - 3 



In the Lower Sonoran Zone from the Mohave and Colorado 

 deserts east to Utah and New Mexico. Common in sandy irri- 

 gated places on the Colorado Desert, where known as Chinch- 

 weed, because of its strong disagreeable odor, similar to that of 

 the Chinch-bug. 



Reported from San Diego, but erroneously so, as pointed ou1 

 by Mr. Parish. 52 



P. ANGUSTIFOLIA Torr. has a coroniform pappus of 4 or 5 

 short squamellae and sometimes 2 slender upwardly scabrous 

 awns in addition (the awned form being var. subaristata Gray) ; 

 heads short-peduncled and more or less fastigiate. Colorado to 

 Lower California and to be expected along our eastern border. 



P. FILIPES Gray may be known by the pappus of 1 to 4 rigid 

 upwardly scabrous awns with usually some very short interposed 

 squamellae; heads on elongated capillary peduncles; first re- 

 ported from "California, Coulter/' but many of Coulter's plants 

 labeled as Californian were collected in Arizona. 



P. COULTERI Gray has a pappus of 2 to 6 retrorsely barbed 

 awns and a puberulent herbage. Likewise reported from Coul- 

 ter's "California" collection, but probably restricted to Arizona 

 and Mexico. 53 



P. LINIFOLIA L. (P. punctata Jacq.) has a pappus of 2 or 3 

 corneous nearly smooth divergent awns. The Synoptical Flora 

 credits it to Southern California by an evident typographical 

 error for Lower California. It occurs in Arizona as the var. 

 marginalis Fernald. 54 



TRIBE 8. ANTHEMIDEAE. MAYWEED TRIBE. 



83. ANTHEMIS L. CAMOMILE. 



Aromatic branching herbs with alternate never entire leaves. 

 Heads solitary on terminal peduncles. Ray-flowers white or 

 yellow; disk-flowers yellow. Involucre hemispheric. Receptacle 

 conical, chaffy toward the summit. Achenes not flattened, gla- 

 brous. Pappus none. 



52Zoe v. 120 (1901). 



ssCoville, Bot. Gaz. xx. 528 (1895). 



54Froc. Am. Acad. xxxiii. 85 (1897). 



