PEA FAMILY 287 



Tax. note. — The number of species here described for California has been increased by three 

 over the number recognized in the Manual of Flowering Plants of California and an attempt has 

 been made to define them more sharply as geographic and ecologic entities. In the diagnoses it 

 is to be understood that the ovary is glabrous unless described otherwise. 



A. Heads with an involucre. 

 1. Corolla conspicitotjslt inflated ; annuals. 

 Involucre present. 



Involucral lobes 3 to 9 (commonly about 6 lines long) ; heads 1 to 2 inches wide ; flowers 



cream-color or yellowish 1. T. fucatum. 



Involucral lobes 2 lines long or less ; heads 4 to 6 lines wide ; flowers purple, reddish or white. 



2. T. amplectens. 

 Involucre reduced to a ring, or subobsolete 3. T. depauperatum. 



2. Corolla not inflated (somewhat inflated in no. 12) ; annuals except nos. 6 and 10. 

 a. Involucre a flat or spreading dish with variously shaped margin (sometimes of 



separate segments). 

 Calyx-teeth dilated and either tridentate or simple. 



Plants strictly glabrous ; stems commonly not fistulous 4. T. tridentatum. 



Plants pubescent and clammy; stems fistulous 5. T.obtusiflorum, 



Calyx-teeth not dilated but subulate, entire. 

 Heads large ; stems commonly thick. 



Flowers large, 6 to 7 lines long, purple to pinkish, lighter at the top ; heads very densely 



flowered ; perennial 6. T. wormshjoldii. 



Flowers smaller (mostly 3 to 5 lines long), dark purple, cream-tipped; heads less densely 



flowered ; annual 7. T. appendiculatum. 



Heads commonly small ; stems slender. 



Annual ; stipules with margin laciniately toothed or divided. 



Corolla much longer than calyx; involucre with laciniately toothed lobes 



8. T. variegatum. 

 Corolla little longer than calyx ; involucre cleft nearly to base into deeply laciniate 



divisions 9. T. oliganthum. 



Perennial; stipules with margin entire or nearly so (serrate in one var.) ; corolla 2 to 3 

 times as long as calyx ; involucre cleft to base or nearly so 10. T. monanthum. 



6. Involucre campanulate to bowl-shaped. 

 Lobes of involucre toothed. 



Calyx-teeth many-forked, glabrous 11. T. cyathiferum. 



Calyx-teeth all or all but one simple, hairy or ciliate. 

 Calyx-teeth plumose, the upper one forked. 



Heads 4% to 7 lines wide; mouth of calyx-tube symmetrical 12, T. barbigerum. 



Heads 9 to 13 lines wide ; mouth of calyx-tube oblique 13. T. grayi. 



Calyx-teeth ciliate, all simple - 14. T. microdon. 



Lobes of involucre entire; calyx-teeth broadly subulate with scarious margins 



15. T. microcephalum. 



B. Heads naked or with involucre reduced to a vestigial ring or bract (see also no. 3) . 



1, Perennials 

 a. Flowers on pedicels mostly 2 to ^% lines long, recurved in fruit; leaflets obcordate, orbicular 



or obovate. 

 Peduncles not recurved at apex, the globose fruiting heads, therefore, erect. 



Stems creeping, rooting at the nodes; flowers white or pinkish 16. T. repens. 



Stems erect or ascending, not rooting at the nodes: flowers pink 17. T. hybridum. 



Peduncles recurved at apex, the fruiting heads thus appearing as if horizontal 18. T. breweri. 



b. Flowers sessile or on pedicels y^ to 1^2 lines long ; leaflets obovate to linear. 



Heads peduncled ; mostly Sierra Nevada and extreme northern California. 



Peduncles usually abruptly recurved at apex, the heads thus appearing more or less horizon- 

 tal ; flowers reflexed. 



Leaflets 3 to 7 ; calyx-teeth not plumose, sparsely short-hairy 19. T. lemmonii. 



Leaflets 3 ; calyx-teeth densely plumose, the young heads appearing woolly 



20. T. eriocephalum. 



Peduncles remaining erect, the fruiting heads, therefore, erect. 

 Flowers not reflexed or only tardUy so. 



Leaflets 3 21. T. longipes. 



Leaflets 5 to 7, rarely 3. 



Calyx densely silky-villous, the filiform segments plumose. 

 Heads exceeding the leaves ; stipules ovate-oblong. 



