690 Rvdberg: Rocky Mountain flora 



cosiis h. Gray. A careful reading of the original short description 

 of Gray*s variety will reveal to anyone that it cannot apply to P. 

 XyliiS, As P, siiffvutescens was based exclusively on Gray's variety, 

 it can by no means be called a nouien nudum as Professor Nelson 

 is inclined to regard it. To it I refer also P. procumbens Greene 

 published nearly two months later. 



Pentstemon Thompsoniae (A. Gray) Rydb. sp. nov. 



Pentstcmon ptiDiilus Thompsoniae A. Gray, Syn. FL 2' : 269. 



1878. 



This is a very distinct species, not related to P. ptnnilus. Dr. 

 Gray at first ^ placed Pentstemon pumilus with P. albidus, P.Jamesiiy 

 and P. cristatus, i, <?., in a group to which it rightly belongs, not- 

 withstanding its small size. Afterwards,! he transferred it wrongly 

 to the P. caespitosiis group, with which it has little in common. 

 P. Thompsoniae on the contrary belongs to this group and is a 

 close relative to P. caespitosus. I suspect that Dr. Gray has 

 redescribed the true P. pumiltts Nutt. under the name P. miser.\ 



I have not seen the type of the latter but the description agrees 

 well with P. pumilus, 



Pentstemon platyphyllus sp. nov. 



Pentstemon heteropliylhts latifolhis S, Wats. Bot. King's Exp. 

 222. 1871. Not P. /^r^z/b/mj Hoffm gg. 1824. 



Dr. Gray in the Synoptical Flora § refers this doubtfully to 

 Pentstemon arMveiis Jaffrayaniis Gray {P. /affray anus Hook.). The 

 two resemble each other in leaf form and general habit, but there are 

 differences important enough to make them distinct species. I am 

 also inclined to think that P. Jaffrayaniis is specifically distinct 

 from P. aznreus, although I have not seen any authentic specimen 

 of the latter. The leaves in P. Jaffrayanns are strongly glaucous 

 and the upper are subcordate and clasping at the base ; the calyx- 

 lobes are oval or obovate, abruptly short-acuminate or mucronate 

 with an erect tip ; the anthers are somewhat hirsutulous at the 

 sinus as well as papillose-hispidulous on the margins ; and the sterile 



* Proc. Am. Acad. 6 : 67. 1862. 

 tSyn. FL 2^: 269. 1878. 

 X Syn. FI. ed, 2, 2» : 441. i886. * 

 ?2^: 272. 1878. 



