310 



LEGUMINOSiE. 



herbage glabrous and flaccid; stems decumbent, stout, sometimes 

 fistulous, 5 to 17 in. long; leaflets obovate-oblong, obtuse, pectinate- 

 denticulate, f to 1 in. long; heads hemispherical, 1 in. broad; involu- 

 cre 6 to 9 lines broad, laciniately cleft, the tooth-like segments 

 aristate; flowers rose-color; calyx-tube scarious, 10-nerved, the alter- 

 nate nerves less prominent; teeth gradually attenuate, longer than 

 the tube, all entire, or some of them setaceously divided; banner 

 elliptical, deeply emarginate. 



Rather frequent along streams or about springy places or bordering 

 the edges of salt-marshes: Howell Mountain; Denverton; San Fran- 

 cisco. May-June. 



17. T. barbigerum Torr. Prostrate or ascending, the branches 

 2 to 4 in. long; petioles and peduncles pubescent; leaflets elliptic- 

 obovate to obovate-oblong, retuse or obtuse, 3 to 5 lines long; stipules 

 scarious, broadly ovate, laciniate; involucre as broad as heads, shortly 

 lobed and setaceously many-toothed; heads 4 to 5 lines wide; pedun- 

 cles long (1J to 2f in.); calyx-tube short, thin and at length scarious; 

 teeth setaceous-awned from a short triangular base, plumose, some- 

 times 2 to 3-parted, the lower usually exceeding the purple corolla; 

 pod 2-seeded. 



San Francisco southward to Santa Cruz. Not common. May. 



18. T. Grayi Loja. Erect or ascending, 8 to 16 in. high, villous 

 with spreading hairs; leaflets obovate to cuneate-oblong, obtuse or 

 acute, sharply serrate, 9 to 12 lines long; heads long-peduncled, nearly 

 or fully 1 in. broad; involucre as broad as heads, deeply lobed and seta- 

 ceously toothed; calyx-tube villous, 10-nerved; teeth linear-subulate 

 from a triangular base, plumose, frequently reddish, equaling the 

 dark red-purple corolla. 



Near the coast but infrequent: San Bruno Hills and northward. 



19. T. fucatum Lindl. Sour Clover. Diffuse or decumbent, 

 glabrous, somewhat scabrous above, very stout and succulent, much 

 branched, the branches \ to 2 ft. long; leaflets obovate to inversely 

 deltoid, mostly cuneate at base, pectinate or spinulose-serrate or 

 nearly entire, £ to 1 in. long; heads very large, 1 to If in. in 

 diameter, about 12 to 20-flowered; calyx-tube campanulate, 1 to 1£ 

 lines long, not longer than the teeth, the two upper teeth very short; 

 corolla cream-color, fading pinkish, 7 to 10 lines long; keel-petals 

 frequently with a dark purple spot; legume with a rather long stipe; 

 seeds nearly smooth. 



Common in fow and often alkaline fields: Sacramento and San 

 Joaquin Valleys; Coast Ranges (Napa Valley, Oakland, Santa Cruz 

 and Hollister, Setchell, and elsewhere). May-June. The calyx is 

 very variable in the relative length of the teeth and tube, and an 

 attempt has been made to separate as species, various dwarf and 

 robust soil forms, the species being obliged for their diagnoses to the 

 calyx character and to the habit. These forms are here named as 

 ecological varieties. 



Var. flavulum (T. flavulum Greene). As large as the species 

 but somewhat more slender; heads smaller; calyx-teeth slender- 



