396 POLYGONACEAE 



outer lobes orbicular with a short narrow claw, the 3 inner ovate, smaller, 

 minute; stamens 9. 



Mohave Desert: Muroc (Yucca), K. Brandegee. A very distinct species. 



Eefs. CHORIZANTHE SPINOSA Wats. Bot. Cal. 2: 481 (1880), type loe. Mohave Desert, 

 Lemmon, not "San Bernardino"; Parish, Zoe, 5: 113 (1901). 



17. C. orcuttiana Parry. Stems several from the base, prostrate, 1 to 4 

 inches long, sparingly dichotomous ; herbage thinly pubescent ; leaves spatulate 

 or narrowly oblanceolate, mostly in a basal tuft; involucres scattered along 

 the branches and terminal; involucral tube nearly 1 line long, cylindric but 

 3-angled, 3-toothed, not or only obscurely reticulated, its stout teeth nearly or 

 quite horizontally spreading and as long as the tube; flowers usually 1, pedi- 

 celled; "calyx-lobes equal, its tube narrowly turbinate; stamens 9 or fewer." 



Point Loma, San Diego (only known station). Quite like C. polygonoides in 

 habit but its involucres very different. 



Kef. CHORIZANTHE ORCUTTIANA Parry, Proc. Davenp. Acad. 4: 54 (1884), type loc. San 

 Diego, Orcutt. 



18. C. polygonoides T. & G. Dichotomously branched, forming mats 5 to 

 10 inches across ; basal leaves oblanceolate, contracted to a petiole, % to 1% 

 inches long; bracts in pairs, oblanceolate or obovate, resembling the leaves of 

 the basal rosette and becoming smaller towards the ends of the branches; 

 involucres obpyramidal, strongly 3-angled, corrugated between the ribs, with- 

 out scarious margin, solitary or in 2s or 3s, the tube 1 to l 1 /^ lines long, the 

 3 larger lobes as long and with alternating short and inconspicuous ones at 

 base. 



Central Coast Ranges ; northern Sierra Nevada foothills ; San Diego Co. The 

 floristic distribution seems erratic, and the range is therefore, in all proba- 

 bility, insufficiently known. 



Loes. Big Valley, Modoc Co., Baker $ Nutting; Scotts Valley, Lake Co., Tracy 1724; 

 Howell Mt., Tracy 1564; Tamalpais, K. Brandegee; Oakland Hills, K. Brandegee; Sheep 

 Eanch, Calaveras Co., Davy 1612; San Diego, Brandegee. 



Eefs. CHORIZANTHE POLYGONOIDES T. & G. Proc. Am. Acad. 8: 197 (1870), type loc. 

 Placerville, Volney Eattan; Jepson, Fl. W. Mid. Cal. ed. 2, 130 (1911). 



19. C. rigida T. & G. Stem erect, 1 to 3 inches high, simple or very shortly 

 branched, densely packed with short involucre-bearing branchlets, or some- 

 times diffusely spreading and forming a spiny mat 6 to 11 inches broad ; leaves 

 on the primary stem or branches round-ovate to obovate, 4 to 12 lines long, on 

 petioles 1 to l 1 /^ times as long, those of the branchlets lanceolate or subulate, 

 spine-tipped, becoming hard and rigid, the involucres in clusters in their axils ; 

 involucral tube short, about 1 line long and as broad, strongly and acutely 

 3-angled and strongly reticulated between the angles, its lobes 3, foliaceous, 

 ovate to lanceolate, spreading, unequal, very unequal also on different invo- 

 lucres on the same plant, 3-ribbed and reticulate on back, 1 to 8 lines long, 

 tipped with straight short spines; flower pedicelled, yellowish; calyx-tube 

 narrow, abruptly expanded into the short throat and limb, its lobes oblong, 

 short, very hairy on back, scarcely exserted ; stamens 9, inserted at throat. 



Colorado Desert and the eastern Mohave north to Inyo Co. Southern 

 Nevada; Arizona. Lower California. Apr .-May. One of the most character- 

 istic annuals on the driest stony hills where there is little or no other vegeta- 

 tion. 



Locs. Keeler, Brandegee; Argus Mts., Hall fy Chandler 6897; Ludlow, Hall 6109; Calico 

 Wash, Jepson 5388, 5409; Barstow, Jepson 4792 (plants prostrate forming a spiny mat); 

 Chuckawalla Spr., Hall 5906; Borego Spr., Brandegee. 



Eefs. CHORIZANTHE RIGIDA T. & G. Proe. Am. Acad. 8: 198 (1870). Acanthogonum 

 rigidum Torr. Pae. E. Eep. 4 s : 133 (1857), type loc. Williams Eiver, Ariz., Bigelow. 



