52 DAVENPORT ACADEMY OF NATURAL SCIENCES. 



4. C. Spinosa, Watson, 1. c. Erect or decumbent, 2-4 inches broad, 

 hairy-pubescent, branching from the base; radical leaves oval obtuse, 

 villous-pubescent beneath, with scattered ai)pressed hairs above, petioles 

 about as long as the blade, margined and revolute when old, expanding 

 at base to a broad, clasping insertion ; cauline bracts ternate, or oppo- 

 site, connate, narrow, reflexed, and rigidly awned; involucres pubes- 

 cent, divisions very unequal, of one long rigid awn, two others about 

 half the size, and one or two smaller, intermediate, all straight, the cen- 

 tral axilary involucre much the largest, closely adherent, with smaller 

 ones crowded, in irregular clusters, frequently infertile and deciduous; 

 flowers 2-3, unequally developed, the more perfect longer pedicelled, 

 and more or less exsert, the smaller usually imperfect, perianth tubular, 

 outer segments spathulate-orbicular to obcordate, with a short claw, the 

 inner one half shorter and ovate; stamens 9, anthers oblong, styles 

 long and slender, akene broadly triangular, beaked; embryo with yel- 

 lowish green cotyledons, and long radicle. 



Habitat: Mojave Desert, J. G. Lemmon, 1880; C. C. Parry, 1881; 

 Parish Brothers, 1882. Softly pubescent when young, becoming rigid 

 spinescent when old, connecting the previous species of this section 

 with the more ordinary forms of Ejichorizanthe. 



§ 2. Acanthogonum, Torr. & Gray. Involucres i flowered, broad- 

 ly triangular-turbinate, sharply costate, and reticulate on the sides; di- 

 visions 3-5, the three principal ones unequal, divergent, terminating in 

 rigid straight or uncinate awns; involucral bracts foliaceous, cuspidate 

 or rigidly linear-spinescent ; flowers short pedicelled; stamens 6-9, with 

 short filaments, inserted on the throat. 



5. C. polygonoides, Torr. & Gray, Watson, 1. c. Procumbent, 4-10 

 inches broad, branching from the base, smooth or sparingly pubescent, 

 stems short, jointed, and fragile; radical leaves narrowly spathulate, 

 obtuse, gradually tapering into a slender petiole widened at the base, 

 cauline and involucral bracts opposite and connate, less foliaceous and 

 more accuminate above; involucres coriaceous and reticulated, spar- 

 ingly clustered in the axils, more or less hairy pubescent, broadly trian- 

 gular-turbinate, sharply 3-costate, with broadly divergent divisions, ter- 

 minating in uncinate awns, 2 intermediate, smaller; flowers single, ped- 

 icellate, shortly exsert, tube narrow and slightly contracted at the throat,- 

 segments equal, obtuse or truncate, ciliate-hairy externally ; stamens 6, 

 with short filaments, inserted on the throat, anthers broad-oval, bright 

 red, soon deciduous; styles short, erect; akene broadly triangular, 



