522 



FABACEAE 



Heads involucrate. 



Flowers not inflated; involucral bracts united. 

 Involucre cup-shaped. 

 Involucre rotate. 

 Flowers inflated in age; involucral bracts distinct, sometimes much reduced. 



I. Agraria. 



Heads 8-12 mm. long; standard dilated, not folded over the pod. 

 Heads 4—6 mm. long; standard not dilated, folded over the pod. 



X. Cyathifera. 

 XI. Involucrata. 



XII. FuCATA. 



1. T. procumbens. 



2. T. dubiutn. 



II. Gracilenta. 



Calyx not ciliate on the margins. 



Plants especially the peduncles and calyx pubescent. 3. T. bifidum. 



Plants glabrous throughout. 



Leaves obovate and retuse at the apex, the serrations not setaceous. 4. T. gracilentum. 



Leaves narrowly lanceolate, acute, aristate, the serrations conspicuously setaceous. 



5. T. P aimer i. 



Calyx conspicuously ciliate on the margins, plant otherwise glabrous or nearly so. 6. T. ciliolatum. 



III. Repentia. 



Calyx and whole plant villous-pubescent. 



Calyx glabrous or sparsely pubescent, plant otherwise glabrous or nearly so. 



Stems ascending; flowers pink; calyx pubescent in the sinuses between the teeth. 



Stems creeping; flowers white; calyx glabrous or sparsely pubescent at the base. 



7. T. Breweri. 



8. T. hybridum. 



9. T. rep ens. 



IV. Altissima. 



Flowers distinctly pedicellate, reflexed in age. 



Rachis of the head flower-bearing to the apex. 



Heads large, 2 cm. or more high; standard broad, rounded at apex. 



Corolla red; leaflets oblong to oblong-lanceolate, pallid and strongly nerved. 



10. T. Beckwithii. 

 Corolla white; leaflets ample, ovate, bright green and thin. 11. T. Howellii. 



Heads small, 10-15 mm. high; standard narrow, acutish. 12. T. Bolanderi. 



Rachis prolonged above the flowers as a sterile projection, especially evident in the older heads. 



13. T. productum. 

 Flowers sessile, not evidently reflexed in age; calyx more or less distorted in age. 14. T. Douglasii. 



V. LONGIPEDIA. 



Calyx conspicuously plumose, with widely spreading hairs; standard rounded at apex; flowers strongly reflexed; 



peduncles often recurved at apex. IS. T. eriocephalum. 



Calyx merely hairy, with ascending or appressed hairs; standard acute; peduncles erect. 



Flowers pedicellate, reflexed in age. 16. T. oreganum. 



Flowers sessile or subsessile, not relieved in age. 17. T. longipes. 



VI. Macrocephala. 



Flowers on very short pedicels, purple, somewhat reflexed at age only in Thompsonii. 



Corolla 2 cm. long; leaflets denticulate. 



Leaflets linear-lanceolate, the longer 4-7 cm. long; calyx-teeth thinly villous-pubescent with somewhat 

 appressed hairs. 



Leaflets obovate, 1-2 cm. long; calyx- teeth densely plumose, with widely 

 spreading hairs. 



Corolla 1 cm. long; leaflets entire. 



Peduncles densely villous, shorter than the leaves. 



Peduncles sparingly pubescent, well exceeding the leaves. 



Flowers on pedicels about 2 mm. long, yellow; leaflets denticulate. 



VII. Plumosa. 



Only one species. 



VIII. Pratensia. 



Only one species. 



IX. Arvensia. 



Heads cylindrical; flowers red, pink, or white; introduced species. 



Corolla pink or white, 2-3 mm. long, much shorter than the calyx-teeth. 

 Corolla red, exceeding the calyx. 

 Heads globose to oblong-ovoid; flowers purple; native species. 

 Corolla exceeding or about equaling the calyx. 



Heads sessile in pairs in the axils of the uppermost leaves. 

 Heads solitary on evident more or less elongated peduncles. 

 Corolla well exserted. 



Heads globose-ovoid; flowers 15 mm. long. 

 Heads long-ovoid; flowers 8-10 mm. long. 

 Corolla barely or not at all exceeding the calyx. 

 Corolla much shorter than the calyx and fairly concealed. 

 Ovary pubescent. 

 Ovary glabrous. 



23. T. plumosum. 



24. T. pratense. 



25. T. arvense. 



26. T. incarnalum. 



27. T. Macraei. 



28. T. amoenum. 



29. T. dichotomum. 



30. T. albopurpureum. 



31. T. columbinum. 



32. T. olivaceum. 



