288 LEGUMINOSAE 



Stipules sparsely toothed ; heads somewhat spicate ; plants not caespi- 



tose, the stem simple 22. T. macrocephalum. 



Stipules entire; heads capitate-umbellate; plants caespitose, the stems 



and leaves matted, the naked peduncles erect 



23. T. monocnse. 

 Heads not exceeding the leaves, somewhat umbellate; stipules lanceolate, 



entire; stems matted 24. T. andersonii. 



Calyx pubescent, the lanceolate or subulate-lanceolate segments not plumose; 



heads f ew-floAvered ; plants 1 to 3 inches high 25. T. gymnocarpon. 



Flowers reflexed in age. 



Plants sparsely pubescent above 26. T. oreganum. 



Plants glabrous throughout. 



Eachis produced above the heads; leaflets mostly lanceolate to oblong-lance- 

 olate, acuminate, spinulose-serrate 27. T. kingii. 



Eachis not pioduced above the heads; leaflets broader, not acuminate, less 

 deeply toothed. 

 Stems subscapose, the leaves congested at the base; fruiting heads conical, 

 Vi to % inch wide; flowers completely reflexed.. ..28. T. tolanderi. 

 Stems leafy; fruiting heads globose to subglobose, 1 to 1^ inches wide. 

 Leaflets thin, not venulose, ovate-rhombie or ovate ; flowers white, usu- 

 ally all reflexed 29. T. howellii. 



Leaflets thickish, venulose; flowers red, usually only the lower re- 

 flexed 30. T. ieclcwithii. 



Heads not peduncled, subtended by the stipules of the sessile upper leaves; stipules scarious, con- 

 spicuously veined; flowers not reflexed 31. T. pratense. 



2. Annuals 

 o. Flowers pedicellate, in age reflexed. 

 Plants more or less pubescent. 



Petioles shorter than the leaflets ; terminal leaflet on a rachis 1 to 2 lines long, the lateral 

 subsessile (leaves pinnate) ; flowers yellow. 



Heads 3 lines broad; banner not dilated 32. T. dubium. 



Heads 414 to 5 lines broad; banner dilated 33. T. procumhens. 



Petioles as long as or longer than leaflets ; leaflets all subsessile at the same point (leaves 

 palmate) ; flowers white to rose-pink; pubescence confined to peduncles and calyces. 



34. T. bifidum. 

 Plants strictly glabrous. 



Calyx-teeth with bristled or ciliated margins; flowers light pink 35. T. ciliolatum. 



Calyx-teeth with entire margins; flowers rose-red to cream-color 36. T. gracilentum, 



6. Flowers sessile, not reflexed. 



Heads sessile in pairs, subtended by the stipules of the sessile upper leaves 37. T. macraei. 



Heads not sessile. 



Corolla exceeding or about equaling the calyx. 



Heads 7 to 12 lines wide, globose-ovate; corollas well exserted; stem usually one from 



the base 38. T. amoenum. 



Heads mostly 4 to 6 lines wide, cyltndrie or hemispheric to narrowly ovate ; stems 1 to 

 several from the base. 



Corollas well exserted 39. T. dichotomum. 



Corollas barely or not at all exserted 40. T. albopurpureum. 



Corolla much exceeded by the calyx, entirely obscured by the long-plumose calyx-teeth 



41. T. olivaceum. 



1. T. fucatum Lindl. Bull Clover. (Fig. 191.) Stems stout, fistulous, succu- 

 lent, diffuse, 1 to 2% feet long; leaflets rhombic-ovate, 5 to 12 lines broad, broadly 

 dentate, sometimes dentate-setate; heads large, 1 to 2 inches in diameter; involucre 

 5 to 9-lobed, its margins scarious, entire; flowers pedicellate; stipules large, broadly 

 subulate, acuminate, the margins membranous; corolla cream-color tinged with 

 light green, in age inflating and turning a deep pink; keel dark purple; calyx very 

 small, scarious, the teeth short, 5, unequal; pods stipitate, 3 to 8-seeded. 



Low alkaline or brackish clays or on blue adobe, 5 to 3200 feet : throughout cis- 

 montane California. North to Oregon. Apr.- June. 



Note on variation. — Colonies of this species in moist rich soils are usually coarse-stemmed 

 and large-headed; in alkaline soUs slender-stemmed and medium-headed; in stiff hard adobe 

 low-statured and small -headed. And yet, broadly speaking, it may justly be said that in aspect 

 and habit, in character of its vegetative organs and in flowers, Trifolium fucatum is a well- 



