1907] Hall. Composite of Southern California. 169 



surface marked only by the depressions which once surrounded 

 the bases of the achenes, and such a receptacle will appear scrobi- 

 culate, as is often, but not always, the case in Ptilomeris. In 

 B. aristata, of the Ptilomeris section, the receptacle is often as 

 plainly muricate as in species of Eubaeria ; or a portion of the 

 receptacle may be muricate while the remainder is merely scro- 

 biculate, as a result of fusion of the papillae. The receptacle is 

 commonly glabrous in Eubaeria and Dichaeta, glabrous to densely 

 villous in Ptilomeris. It is thus seen that neither pappus nor 

 receptacle furnishes characters upon which to found species, much 

 less sections or genera, and leaf characters are likewise elusive, 

 as may be inferred from the specific descriptions beyond. 



Involucre of only 3 or 4 bracts: ligules obsolete or wanting: pappus of at- 

 tenuate paleae: leaves entire 1. B. microglossa. 



Involucre of more numerous bracts. 



Leaves all linear and entire 2. B. chrysostoma. 



Leaves toothed, cleft, or parted, or some entire. 



Leaves broadly linear to oblong: plants robust: pappus either of two 



sorts or none 3. B. uliginosa. 



Leaves or their divisions filiform or linear 4. B. aristata. 



1. B. microglossa (DC.) Greene, Fl. Fr. 438 (1897). Bur- 

 rielia microglossa DC., Prodr. v. 664 (1836). 



Stems very slender, the plant 5 cm. to 1 or 2 dm. high : her- 

 bage more or less hirsute : leaves linear, 1 to 3 mm. wide or the 

 upper sometimes more dilated: involucre cylindric, 5 to 8 mm. 

 high; bracts only 3 or 4, oblong: receptacle subulate: pistillate 

 flowers 1 to 3, their ligules shorter than the styles or wanting: 

 disk-flowers not over 15 : achenes fusiform-linear, flattish, sparsely 

 short-pubescent : pappus-paleae 2 to 4, attenuate-subulate. 



Andreas Canon, near Palm Springs, Colorado Desert, Apr., 

 1882, Parish, no. 747; San Luis Obispo Co. to middle California, 

 on low ground. 



2. E. chrysostoma F. & M., Ind. Sem. Hort. Petrop. ii. 29 



(1835). GOLD FIELDS. 



Plant low and with unbranched stems when growing in poor 

 or dry soil; becoming robust, profusely branched, and 10 to 25 

 cm. high under favorable conditions: herbage strigulose to hir- 

 sute : leaves narrowly linear, 3 mm. or less wide, entire : in- 



