198 FABACEAE. 



Flowers about 8 mm. long. 6. L. parviflorus. 



Flowers about 6 mm. long. 



Plant vivid green, not at all canescent. 7. L. floribundus. 

 Plant dark green ; inflorescence and young leaves canescent. 



8. L. myrianthus. 

 Plant light green ; stem more strigose ; leaves more or less silvery ; 



flowers light blue or white. 



Flowers about 8 mm. long; leaflets linear. n. L. tenellus. 



Flowers 10-12 mm. long; leaflets oblanceolate. 



12. L. decumbens. 

 2. Leaves permanently pubescent above. 



Plant green ; leaves appressed-pubescent or slightly silky ; pubescence of 



the stem long, spreading. 9. L. comatus. 



Plants more or less canescent or silvery ; at least the upper part of the stem, 

 inflorescence and the lower surface of the leaves densely silky or villous. 

 Stem appressed-pubescent. 



Calyx distinctly spurred at the base. 10. L. argophyllus. 



Calyx not spurred, but sometimes rather strongly gibbous at the base. 

 Flowers less than 12 mm. long; banner not conspicuously light- 

 spotted. 



Pubescence of the leaves finely silky, short, not dense, and per- 

 fectly appressed. 

 Pubescence of the inflorescence finely appressed-silky ; leaflets 



oblanceolate. 13. L. argenteus. 



Pubescence of the inflorescence looser and spreading. 



12. L. decumbens var. 

 Pubescence of the leaves dense, longer and often looser. 



14. L. oreophilus. 

 Flowers 12 mm. or more long; banner with a large conspicuous light 



spot. 

 Stem few-leaved, only slightly exceeding the long basal leaves. 



15. L. humicola. 

 Stem very leafy, many times exceeding the basal leaves. 



1 6. L. sericeus. 

 Stem with dense pubescence of spreading usually short hairs. 



Corolla blue; banner with a light spot. 17. L. Bakeri. 



Corolla at first white ; the banner changing into purple ; no light spot. 



1 8. L. dichrous. 

 II. Stem low, less than 3 dm. high, densely cespitose. 



Inflorescence much exceeding the leaves. 19. L. psoralioides. 



Inflorescence not exceeding the leaves. 



Racemes very dense and short, sessile ; bracts lanceolate, about equalling 



the flowers ; pubescence rather appressed. 20. L. caespitosus. 



Racemes elongated ; bracts subulate, exceeding the flowers ; pubescence 



loose. 21. L. Watsoni. 



B. Annuals ; cotyledons after germination sessile, clasping the stem ; pod 2-seeded. 

 Raceme dense, subcapitate ; lower lip of the calyx 2-3-toothed. 

 Plant almost stemless ; lower lip of the calyx oval or ovate. 



22. L. brevicaulis. 

 Plant with a distinct leafy stem ; lower lip of the calyx oblong-lanceolate. 



23. L. Kingii. 

 Racemes more elongated and less dense ; lower lip of the calyx entire. 



24. L. pusillus. 



1. Lupinus amplus Greene. In the mountains of Colo. Alt. about 8000 

 ft. Cerro Summit; below Steamboat Springs. 



2. Lupinus ammophilus Greene. (L. Sitgreavesii Coult. Man., in part.) 

 In the mountains of Colo, and N. M. Alt. 6000-7000 ft. Los Finos (Bay- 

 field) ; Mancos; Durango. 



