PEA FAMILY. 305 



Calyx-segments very mucli longer than the corolla and often so 

 plumose as to quite conceal it; heads dore-colored or olive-green, 

 ovate, with broad truncate base or more hemispherical in the 



vars 6. T. columbinum. 



Perennial; calyx-teeth sparingly hairy; flowers red 



6. T. pratense. 

 iJ'lowers pedicellate, at length reflexed; calyx-teeth subulate or setaceous, 

 not plumose. 

 Calyx-teeth rigid-ciliolate; podl-seeded. . . 7. T. ciliolatum. 



Calyx-teeth not ciliolate. 

 Leaflets narrow as compared with the next; the notch at apex mucron- 

 ulate; rachis not prolonged, or appearing only as a minute point; 



god 1-seeded S. T. Mfidum. 

 ets obcordate, the notch at apex usually not mucronulate; rachis 

 prolonged through the head as a sterile point about 3 lines long; 

 pod 2-seeded . 9. T. gracilentum. 



B, Heads subtended by an involucre, or by a mere ring in no. 21. 



Corolla not becoming inflated. 

 Involucre cup-shaped, not deeply lobed, membranous at least at base; 

 flowers developing equally all around. 

 Lobes of the involucre toothed ; teeth of the calyx much shorter than 



the tube 10. r. microdon. 



Lobes of the involucre entire; teeth of calyx longer than the tube. . 



11. T. microcephaltcm. 

 Involucre flat, rather deeply lobed, the lobes laciniately toothed; flowers 

 commonly blooming flrst on one side and the heads therefore one- 

 sided. 

 Annuals. 

 Herbage mostly glabrous. 

 Calyx-teeth entire. 

 Stems decumbent or ascending; leaves oboyate or oblong-oblan- 



ceolate ; heads mostly 3 to 6 lines broad . 12. T. variegatum. 



Stems erect, these and the peduncles almost filiform; leaves 



linear ; heads 2 to 3 lines broad ... . 13. T. oliganthum. 



Calyx-teeth not entire 14. T. tridentatum. 



Herbage soft-pubescent and clammy; flowers whitish. 



15. T. obtus-iflorum. 

 Perennial; herbage glabrous; flowers rose-color; banner elliptical, 



deeply emarginate 16. T. Wonnskjoldii. 



Corolla conspicuously inflated in age, the petals withering-connivent by 

 their apices and forming a bladder-like sac to the growing pod. 

 Involucre broad, setaceously many-toothed; calyx-teeth awn-like, plu- 

 mose ; corolla red-purple. 

 Pedunoleslia to 2^1n. long; involucre shallowly lobed, glabrous . . 



17. T. barbigerum. 

 Peduncles 3 to 7 in. long; involucre pubescent, deeply lobed 



18. T. Oraijl. 

 Involucre deeply parted into entire lobes ; calyx-teeth not plumose. 



Involucral lobes 3 to 9 (commonly about 6) lines long; heads large; 

 flowers cream-color or yellowish; pod stipitate; seeds nearly 



smooth 19- y- fucatum. 



Involucral. lobes 2 lines long or less; heads small, Um. m diameter or 

 less; flowers purple, reddish or white; pod sessile; seeds tubercu- 



late or rugose ,.-,•??■ T.amplecUns. 



Involucre obscSete or reduced to an entire or slightly lobed herbaceous 

 ring; leaflets serrate (or laciniate-toothed in one ol the vars.) . . . 



21. T. depauperatnm. 



1. T. Macraei H. & A. Plant much branched, the branches 

 decumbent or almost prostrate, 4 to 6 in. long; herbage vlllous- 

 pubescent; leaflets cuneate-oblong, obtuse, denticulate above the 

 middle, 3 to 5 lines long; heads nearly or quite sessile, solitary or 

 often occurring as a terminal pair, ovate, 4 or 5 lines high; calyx- 



22 



