Nelson: New Plants from Wyoming 129 



few to numerous on the crowns, the blade oblong or oblanceo- 

 late, irregularly, coarsely, pinnatcly toothed, acute at apex, from 

 sparsely hirsute to green and glabrous on the faces, canescently 

 hh'sute on the margins and midrib, 3—5 cm. long, on petioles of 

 about equal length : flowers few, calyx-tube equaling or but little 

 shorter than the leaves, hirsute-pubescent, calyx lobes pinkish, 

 lanceolate, glabrous but for a pubescent line down the middle, 

 2-2.5 ^^^^- Ic)"g ' petals white, changing to pink (always drying 

 pink), broadly obcordate, 2-3 cm. long ; stamens but slightly un- 

 equal, the filaments but little longer than the anthers : capsule 

 sessile, oblong or narrowly ovate, obscurely tubercled on the obtuse 

 angles, 15-20 mm. long: seeds in two rows, crowded, brown or 

 nearly black, irregularly obovate. 



That this is the suppressed Ooiothcra moiitana there can be little 

 doubt. Its distinctness was evident to Nuttall and must be to every 

 one who sees it in the field. Though I have distributed it as 0. 

 cacspitosa Nutt. (nos. 58 and 1221), the two species need never be 

 confused. It was the evident distinctness of the two that led to 

 the unfortunate distribution of the true 0. caespitosa (nos. 926 and 

 1274) also under the wrong name. 



In looking through this species cover in the Herb. Mo. Bot 

 Garden, I found some unnamed specimens as follows : By Hay- 

 den, two near the mouth of Wind River, May 20, i860; one, 



F 



Wind River Valley, June 29, i860 ; one, Jackson's Hole, June 12, 

 i860; by Dr. C. M. Hines, two from the Valley of the Yellow- 

 stone, Montana (?), i860, all of which are, without doubt, good 

 PacJiylopJius inontanas. 



This plant differs strikingly from P. cacspitosus (Nutt.) Raimann 

 in its smaller size, its thicker, smaller leaves, smaller flowers, shorter 

 calyx-tube, as well as in its root characters and habitat. It has 

 been known to me for a number of years and I have never secured 

 it except on the naked red, gravelly-clay slopes of the foothills. 

 Here the large white flowers are very conspicuous against the red 

 background to the night-flying insects which undoubtfuUy pollin- 

 ate it. The changing to pink follows upon their fertilization and 

 takes them out of competition with their neighbors. 



My collection, of this species, no. 1896, Laramie, June 3, 1896, 

 may be cited as typical. 



