268 Nelson : New Plants from Wyoming 



10-20 cm. long, floriferous nearly to the base but more remotely 

 so downward ; even the uppermost bracts leaflike : nutlets all 

 alike, the aculeae connected at base and forming a narrow winglike 

 margin, minute papillose on all sides. 



The recent segregation of the allied forms of L. occidentalis 

 (Wats.) Greene (Pittonia, 4 : 93-97) seeme the most rational treat- 

 ment that this group has received. Probably as more specimens 

 are accumulated, the descriptions as drawn may need to be made a 

 little more elastic in order to include some forms that show environ- 

 mental variations. The variety here proposed, however, seems to 



» 



be more than that. It is a plant of the arid plains, in sandy soil, 

 among the underbrush. No. 4502, Evanston, June 4, 1898, and 



j 



J Lappula erecta 



Annual, possibly sometimes biennial, with a vertical or ascend- 

 ing tap root : stems 2-5, more rarely only one, simple, erect, more 

 or less paniculately branched above, 2-4 dm. high, cinereously stri- 

 gose-pubescent, moderately appressed : crown leaves rather nu- 

 merous, rosulate, oblanceolate, short-petioled, variable in size but 

 rather small : stem leaves broadly linear or linear-oblong, sessile 

 by a broadish base or tapering into a short petiole, 1-4 cm. long, 

 pubescence a little harsher than that of the stem and the base of 

 the hairs more distinctly pustulate : spikes panicled, from rather 

 open to much crowded ; bracts resembling the leaves, but 

 smaller, somewhat ciliate on the margins : nutlets all alike, mi- 

 nutely and densely muricate-tuberculate on all sides with the mu- 

 riculations in the median line of the dorsal face a little more prom- 

 inent than the others, a single marginal series of about 10 aculeae 

 which are distinct to an obscure marginal ridge. 



On account of the confusion that has existed in regard to Z„ 

 Texana, as understood by Dr. Greene (Pittonia, 4 : 94), and L. occi- 

 dentalis, according to the same authority (/. c, 97), this species 

 has long remained unnamed, though undoubtedly often col- 

 lected. It has been ticketed at different times with both of the 

 foregoing names, and perhaps as often as L. Lappula. f To the lat- 

 ter it bears much resemblance as to habit, but the nutlets at once 

 distinguish it. It may also be compared to the recent L. collima 

 Greene, but from this it is also very distinct by the nutlets, a dif- 

 ferent pubescence, and the less noticeably rosulate leaves. 



July 



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