220 LEAFI.ETS. 



simple stiflf hairs visible under a lens : leaves neither very- 

 rigid nor pungent, sessile along the branches and appearing 

 almost digitate by their 4 or 5 long and linear segments : ra- 

 cemes larger but flowers smaller than in the type species, and 

 white : pods unknown. 



Known only as collected by Mr. J. B. Leiberg on Dry 

 Creek, Malheur Co., Oregon, 21 May, 1896. The locality is 

 in extreme eastern Oregon, remote from the range of P. Fre- 



montii. 



PoivYCTENiUM BisuLCATUM. In habit quite like P. Fre- 

 montii, with a similarly dense tuft of acerosely dissected basal 

 leaves, but the plant smaller, also quite cinereous with a cop- 

 ious but very minute and short dendritic pubescence, this 

 extending to the pedicels : siliques short, only 3 or 4 lines 

 long, linear-oblong, strongly obcompressed, each valve sunken 

 into a shallow furrow on either side of the mid vein. 



Collected so far only by Thomas Howell, in Silvies' Valley, 

 of the Blue Mountains. Oregon, 24 May, 1885. Readily dis- 

 tinguished by its dense pubescence and short, much flattened 

 and bisulcate pods. The plant is also small, the most perfect 

 specimens less than 3 inches high. 



P1.ANODKS is a generic name well suited to a cruciferous 

 type which for more than two centuries past, under the leader- 

 ship of a number of systematists, has wandered from one 

 genus to another, at home now^here, until one admit it as sui 

 generis. The most unnatural place ever assigned it by any 

 one, is that w^hich it is forced into in recent manuals, where it 

 is called Arabis virginica. There is not a group or subgenus 

 of arabis species into which it falls. To put it next the cresses, 

 where Plukenet had it more than two centuries ago, is not at 

 all as bad taxonomy as to call it an arabis. Linnaeus, who 

 knew the type only from Plukenet's figure of a very young 

 plant, could see in it nothing else but a Cardamine, and, alter- 

 ing that author's Virginianum, named it Cardamine Vir- 

 ginica. No one, having an eye to habital resemblances, and 



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