148 University of California Publications in Botany. IT OL - 3 



a 3 to 5-toothed cup encircling the solitary (or rarely 2 to 4) 

 infertile disk-achene. Flowers minute, yellow. Pappus none. 



1. H. minima Gray, Proc. Am. Acad. ix. 189 (1874). Hemi- 

 zonia minima Gray, 1. c. vi. 548 (1865). Harpaecarpus minimus 

 Greene, Fl. Fr. 417 (1897). 



Plant depressed, seldom over 5 cm. high, branched: seed- 

 leaves oval, the others linear, 1 cm. or less long: heads in small 

 glomerules, sessile or on very short peduncles: involucre 2 or 3 

 mm. high: ray-achenes obovate, rounded at summit, either beak- 

 less or with a minute inflexed apiculation. 



Strawberry Valley, San Jacinto Mt., Jepson, and Hall, no. 

 1802 ; Antelope Valley, Davy, no. 2462 ; and in the Sierra Nevada 

 Mts., especially on the eastern slope. To be expected anywhere 

 in the Transition Zone of our district. 



Var. parvula (Gray) Hall, comb. nov. Hemizonia parvula 

 and H. Durandi Gray, Proc. Am. Acad. vi. 549 (1865). Hemi- 

 zonella parvula and H. Durandi Gray, 1. c. ix. 189 (1874). Har- 

 paecarpus parvulus Greene, Fl. Fr. 416 (1897;. Ray-achenes 

 tipped with a short incurved beak : stems sometimes 15 cm. long 

 and the earliest heads slender-peduncled, but plants frequently 

 as depressed as in the species. Transition Zone : Cuyamaca Lake. 

 San Diego Co., Jul. 17, 1906, Mrs. Brandegee; San Bernardino 

 Mts., Parish, nos. 2400, 2086; Wilsons Peak, San Gabriel Mts.. 

 McClatchie; the common form in the Sierra Nevada Mts. and 

 Oregon. 



An extensive series of specimens, mostly from the Sierra 

 Nevadas, exhibits all gradations in the ray-achenes from those 

 with smooth rounded summits to those with conspicuous inflexed 

 beaks. Of the specimens seen from Southern California only 

 those from Cuyamaca are strictly typical of var. parvula, but it 

 reappears just over the line in Kern Co. (Mt. Pinos, Hall, no. 

 6431.) 



55. HEMIZONIA DC. TARWEED. 



Mostly annual or biennial herbs (one of our species some- 

 what woody) with at least the upper leaves alternate. Flowers 

 yellow or white, in mostly numerous heads. Receptacle flat, its 

 bracts deciduous. Ray-achenes obcompressed with broad back, 



