March 30, 1912 27 



Corolla tube al)oiit 2otnni. Ioiik, its lobes 7 to 10 mm. lont;: herbage vil- 

 lous 2a. M. nana lc|)tosi[>l)()n 

 Herbage cinereous uitli a sliorl appressecl pubescence: (lowers pale yellow 

 or white; corolla tube less than i mm. wide. 

 Corolla tube about 20 mm. lonji, its lobes about 6 mm. 



2I). M. nana tenuiflora 

 Corolla tube 15 to iSuim. iou};, its loins usually less than 5mm. 



2C. M. nana arid.i 



II. PVCNANTHAK 



Perennials 

 Leaves not undulate or crisped on the margin 

 Leaves similar on both surfaces 



Herbage cinereous with short, dense, villous-like tomentum; leaves ovate- 

 triangular, irregularly denticulate 3- ^'^- cinerea 

 Herbage glaucous green, or silvery with a minute puberulence, not at all 

 tomentose 

 Stems villous, with spreiiding multicellular h lirs: leaves villous pubes- 

 cent 4- M- australis 

 Stems short pubescent or puberuleut, with recurved hairs 



Leaves bright glaucous green: stems short pubescent, with sleivKr 

 2-celled hairs 

 Bracts purple, broadly to narrowly ovate, acute: stamens glabrous 

 to their bases, these and the corolla throat very sparsely vil- 

 lous: low tufted plants 5- M- epilobioides 

 Bracts lanceolate, herbaceous or nearly so: stamens villous below 

 the middle: corolla throat copiously villous below the insertion 

 of each stamen 5a. M, epilobioides erecta 

 Leaves canescentor silverv: steins pubeiulrnt with recurved subulate 

 or triangular, i -celled hairs 

 Upper surface of leaves with upwardly ajipres.sed or curved hairs 

 Herbage glaucous green with rather sparse, evident puberulence: 



oil ducts on lower surface of leaver crowded 6. M. viminea 

 Herbage silvery, clothed with dense \ery fine puberulence scar- 

 cely perceptible under a strong lens: oil ducts on under sur- 

 face of leaves scattered 7- M. linoides 

 Upper surface of leaves with retrorsely appressed or curved hairs: 

 herbage silvery ( anescent with very dense an I evidt-iit puberu- 

 lence -S. .\1. oblonga 

 Leaves densely hoary tomentose beneath, glabrous or villous above 



Leaves ovate to ovate-oblong, glabrous and dark green al)ove; lateral 



veins impressed on the u[)per surface. 9. .M hypoliruca 



Leaves appearing linear from strongly revolute margln'^. villous above; 

 lateral \eins obscure with no impre->s'on-i above lu. .\I. Janata 



Leaves undulate on margin, somewhat succulen'; stems woolly tomentose 



II. .M. crispa 

 Annuals 



Leaves undulate on margin: bracts anJ caly.N villous: stems pubescent 



J 2. .M. undulata 



