Pipei — Some Western Species of Laihyrus. 



193 



pauciflorus both on account of the size of the flowers and the form of the 

 lea (lets, while Purpus No. 3893 has the leaflets, of utahensis and the flowers 

 a mere trifle smaller. On geographical grounds alone it would seem most 

 probable that these two plants are merely extreme forms of schaffneri, 

 and not southern extensions of the northern forms they so closely simulate. 

 In exactly the opposite way starved forms of pauciflorus in Oregon and 

 Washington become indistinguishable from the normal form of schaffneri 

 as it occurs in Arizona and California. Laihyrus brownii is more variable 

 in leaf form than its larger-flowered analogue tenuior, but it intergrades 

 completely into schaffneri. 



It would seem clear therefore that we have to deal with a widespread 

 species possessing definite variations but also subject according to the 

 environment to fluctuating variations that closely simulate the real varia- 

 tions. Any other interpretation makes it necessary either to provide 

 additional names for some of the forms discussed or else involves the 

 acceptance of overlapping or inconsistent geographical distribution. 



Lathyrus pauciflorus Fernald Bot. Gaz. 19:335. 1894. 

 L. bradfieldianus A. Nelson Bot., Gaz. 54:411. 1912. 

 The typical form of this species occurs mainly in Washington, Oregon 

 and Idaho, but it extends to Colorado. Normally the leaves are sub- 

 coriaceous in texture, but in shade plants, especially from west of the Cas- 

 cade Mountains, are merely firm membranaceous. The type specimen in 

 the Gray Herbarium is Piper No. 14S7, from near Almota, Wash. 



Specimens examined: 

 Washington: Wawawai, Piper May 1S96; 



Almota, Piper No. 2797, Elmer No. 30S; 

 Waitsburg, Horner May 1, 1897; 

 Blue Mts., Horner No. 152; 

 Western Klickitat County, Suksdorf No. 854; 

 Near Wenache, Whited Nos. 1266, 1106, the latter ap- 

 proaching tenuior; 

 Without locality, Vasey No. 257; 

 Upper Nesqually Valley, Allen No. 132; 

 Port Townsend, Wilkes Exped., with unusually thin leaves. 

 Oregon: Blue Mts., Howell May 20, 1885; 



Glendale, M. E. Jones June 19, 1902; 



Trow, Wallowa Forest, Jardine No. 238, a form approach- 

 ing tenuior. 

 Idaho: Lower Clearwater River, Sandberg, MacDougal & Heller 



Nos. 74 and 74a, the latter approaching tenuior; 

 Juliaetta, Henderson No. 2738; 



Silver City, Macbride No. 927, type collection of L. brad- 

 fieldianus. 

 Colorado: Mountains east of Gunnison, L. F. Ward No. 295, cited 



in the original description of L. utahensis Jones. 



