﻿New Plants from Wyoming. — II.* 



By Avex Nelson. 



Thlaspi glaucum (A. Nelson). 



Thlaspi alpestre glaucum A. Nelson, First Rep. Fl. Wyo. 84. 

 1896. 



The perennial, basal part of stem freely branched, the several 

 or many herbaceous stems simple, erect or ascending, 1-3 dm. 

 high ; root leaves numerous, petioled, from oval to oblong or obo- 

 vate, entire or obscurely repand-denticulate ; cauline leaves deltoid- 

 auriculate or oblong, entire, 10-20 mm. long, smooth or even 

 glaucous ; raceme dense in flower, much elongated in fruit (5-15 

 cm.) ; sepals greenish, thin, ovate ; petals white, spatulate, about 6 

 mm. long ; pods obovate, obtuse or emarginate ; pedicels divari- 

 cate, 10-14 mm - long. 



In 1897 an abundance of material of this form was secured, 

 an examination of which leads me to think that it is worthy of 

 specific rank. Its habitat is sub-alpine in open parks or among 

 open spruce timber. It is separated from T. alpestre by its uni- 

 formly larger size, numerous stems, numerous and larger stem 

 leaves, longer pedicels and raceme (in fruit), longer, greenish 

 sepals, etc. 



Type specimen in Herb. University of Wyoming, no. 4176, 

 Battle Lake, August 16, 1897. Prof. Henderson's no. 2893 from 

 Kendrick, Idaho seems to be nearly the same. 



Mextzelia com pacta. 



Annual, 2-2.5 dm - high, numerously and compactly branched ; 

 stems whitish, pubescent, somewhat brittle ; leaves numerous, ses- 

 sile, entire, obtuse, from broadly linear at base to almost oval at 

 summit, generally ovate-oblong, 2-3 cm. long, rough-hirsute, 

 more coarsely and sparsely so above ; flowers yellow, small, nu- 

 merous in compact cymes at the ends of the branches, sessile, 

 about 3 mm. broad ; calyx-lobes lanceolate-ovate, shorter than the 



*I am under obligations to Dr. Underwood for securing for me the com] rison of 

 these plants with specimens in the Columbia Herbarium ; and to Mr. P. A. Rydberg, 

 for making lc h comparison. Mr. Rydberg- well-known familiarity with north- 

 western plants makes hi- examination of these particularly satisfactory. 



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