1922] 



PAYSON — STUDY OF THELYPODIUM AND ITS IMMEDIATE ALLIES 287 



(immature) erect or ascending, terete, subsessile, about 1.5 cm. 



long; style rather stout, 1.5 mm. long, stigma capitate, in age 



2-lobed ; cells of septum short, rectangular, not at all tortuous. 



Distribution: southern Arizona. 



Specimen examined: 



Arizona: Santa Cruz bottoms near Tucson, March 13- April 23, 



David Griffiths 4058 (Mo. Bot. Gard. Herb., type) 

 3 sreneric affinities of this plant are not quite clea 



The 



position of the stigmatic lobes, which are definitely over the 

 valves, excludes the possibility of allying it with those species 

 recently segregated as Thelypodiopsis, and to which the plant 

 bears considerable habital resemblance. Thelypodium is also, for 



excluded for 



um is unlike 



that of any species of Thelypodium known, but it is similar 

 the tvnical seotum of Caulanthus. The rather large stigma tl 



becomes bilobed 



Yellow 



not yet admitted to Thelypodium but is of common occurrence 

 in Caulanthus. The range also would point to the probability 

 that this plant was derived from Caulanthus rather than from 

 the northwestern genus. 



3. C. inflatus Wats. Proc. Am. Acad. 17: 364. 1882; Coville, 

 Contr. U. S. Nat. Herb. 4: 62. 1893; Robinson in Gray, Syn. Fl. 



N. Am. I 1 : 172. 1895. 



Streptanthus inflatus Greene, Fl. Franciscana, 257. 1891. 



Annual, glabrous or sparingly hirsute near the base, sometimes 

 glaucous: stem erect, usually unbranched, stout, becoming con- 

 spicuously inflated above the middle, hollow, 3-6 dm. high: all 

 the leaves with auriculate or clasping bases, the lowermost nar- 

 rowed above the basal lobes: cauline leaves ovate to oblong, 



m 



cm. long: sepals purple in the bud 



anthesis white with purple tips, glabrous, nearly equal in length 

 dorso-ventral pair slightly saccate at the base, scarious-margined 

 acute, 8-10 mm. long; petals white, broadly linear, crisped neai 

 the apex, but little longer than the sepals; filaments stout, longei 

 Dairs coherent for more than half their lengths, shorter than oi 



about 3 mm 



florescence racemose; pedicels 



as- 



pods rather stout, 6-10 cm 



or ascending, subsessile; style very short or obsolete, stigma 

 deeply 2-lobed : cotyledons obliquely accumbent, seed-coat muci- 

 laginous when boiled. 



