1907 ] Hall. Compositae of Southern California. 21 



Involucral bracts conduplicately folded for their whole length and each 



completely enclosing its achene 54. HEMIZONELLA, p. 147. 



Involucral bracts with only the lower portion conduplicately folded, the 



upper portion being flat. 

 Eay-achenes only half -enclosed by the infolded margins of the invo- 



lucral bracts 55. HEMIZONIA, p. 148. 



Eay-achenes wholly enclosed by the infolded margins of the in- 

 volucral bracts, these meeting over the face of the achene. 

 *Disk-achenes without pappus: heads clustered 



56. LAGOPHYLLA, p. 155. 



Disk-achenes usually with distinct pappus: heads large, soli- 

 tary. 



Pappus of 5 to 20 slender awns 57. LAYIA, p. 156. 



Pappus of about 10 broad paleae in 2 series 



58. ACHYKACHAENA, p. 160. 



TRIBE 7. HELENIEAE. SNEEZEWEED TRIBE. 



Herbs, or a few species suffruticose. Leaves alternate or op- 

 posite, in one subtribe punctate with oil-glands. Heads radiate 

 or discoid. Involucral bracts mostly in only one to three series, 

 herbaceous or in a few genera with membranous margins. Re- 

 ceptacle not paleaceous, yet sometimes bristly or hairy. Anthers 

 not caudate. Pappus of paleae, awns, or bristles, or often 

 wanting. 



A. Leaves all opposite: rays present, yellow. 



Bracts of the involucre unequal, broad: pappus none: succulent perennial 

 59. JAUMEA, p. 161. 



Bracts of the involucre equal. 



Involucre cup-like, its bracts united 64. LASTHENIA, p. 167. 



Involucre of distinct bracts. 



Herbage destitute of oil-glands: involucral bracts ovate or oblong 



65. BAEEIA, p. 168. 



Herbage dotted with oil-glands: involucral bracts linear 



82. PECTIS, p. 209. 



B. Leaves alternate, at least above. 

 Pappus present. 



Heads discoid, or the rays if present very inconspicuous. 

 Leaves entire, at least the upper. 

 Flowers yellow. 



Herbage gummy: pappus of 8 to 12 obtuse paleae 



71. AMBLYOPAPPUS, p. 187. 



