Small : North American Polygonaceae 55 



and E. lonchopJiyllum by the long-peduncled involucres in the forks 

 of the inflorescence and from Eriogonum salicinum and the follow- 

 ing species by its campanulate involucres. 



v 



Eriogonum tristichum sp. no v. 



Perennial with woody rootstocks and somewhat elongated 

 caudices (section Corymbosd). Leaves rather few on each caudex ; 

 blades narrowly linear, oblanceolate or linear, 2-7 cm. long, usually 

 revolute, floccose above, densely white-woolly beneath ; sheathing 

 bases of the petioles very densely white-woolly : scapes mainly 

 1-3 dm. tall, glabrous, except at the base, glaucescent, each 

 topped with a compound cyme, the bracts very small except some- 

 times those at the first fork of the inflorescence : involucre turbi- 

 nate, 2.5—3 mm. long, decidedly longer than thick, the lobes 

 broadly rounded, much shorter than the tube : calyxes pink or 

 whitish, becoming 4 mm. long, the lobes obovate to oblong- obovate: 

 filaments sparingly pubescent at the base : ovary and styles glab- 

 rous : achenes about 2.5 mm. long. 



The type was collected at Rosa, Colorado, June, 1899, by C, 

 F. Baker, no. 286 ; other specimens have been collected in Colo- 

 rado as follows : Black Canon, Gunnison, September 1888, Parry. 

 Mesa Verde, September, 1892, Eastwood. Arboles, June, 1899, 

 Baker, 28 j. Parlin, August, 1891, Smith, jj. Eriogonum tris- 

 tichum differs from its nearest relative, E. salicinnm, in its larger 

 and relatively longer involucre and the strongly revolute leaf- 

 blades. 



^Eriogonum Fendlerianum (Benth.) 



Eriogonum microtliecum Fendlerianum Benth. in DC. Prodr. 14 : 



18. 1856. 



This species is related to both Eriogonum corymbosion and the 

 following species but may be easily distinguished from either by 



its larger involucre. 



v/ Eriogonum divergens nom. nov. 



1 



Eriogonum corymbosum divaricatum T. & G. Pacif. R. R. Rep. 2 : 



129. 1855. Not E. divaricatum Hook. 



Like the preceding, this species is related to Eriogonum 

 corymbosum, from which it may be distinguished by the larger 

 more prominently lobed and scattered involucres, and the stiffly 

 spreading branches of the inflorescence. 



