Studies in North American Polygonaceae.— I. 



By John K. Small. 



In 1892 I began a study of the family Polygonaceae with 

 special reference to the genera Polygonum and Eriogonum. Since 

 that time, having been asked by the editors of the proposed Sys- 

 tematic Botany of North America, to prepare the manuscript on 

 the family for the text of that work, I have made a careful review 

 of the group. The results of my studies in Polygonum* and 

 Polygonella\ have already been published and I intend, in the 

 present paper and those of this series to follow, to publish some 

 notes of general interest pertaining to the different genera of this 

 fascinating family. 



My studies have been furthered by the loan of a specimens and 

 types from the Herbaria of the New York College of Pharmacy 

 Harvard University, California Academy of Science, Missouri 

 Botanical Garden and the National Herbarium. Professor Thomas 

 C. Porter has contributed much valuable material of several 

 genera, while Professor Edward L. Greene has generously placed 

 the specimens of several of the species proposed as new in my 

 hands, with the request that I describe them. 



I -NEW SPECIES OF ERI061NUM. 



Eriogonum depauperatum. 



Perennial, slender, pale green. Stem woody, branched; branches 

 tufted: leaves crowded; blades thinnish, linear-spatulate, 2-6 cm. 

 long, obtuse or acutish, revolute, glabrous above r tomentose be- 

 neath ; petioles slender, nearly y 2 as long as the blades : scapes 

 erect, 5-10 cm. tall, simple, sparingly pubescent or glabrate : 

 bracts scale like, lanceolate: involucres 5-8 in a terminal head, 

 tubular or tubular-turbinate, 3.5-4 mm. high, thinly tomentose; 

 segments ovate, acutish, about ^ as long as the somewhat angled 

 tube : calices pink, 2 mm. long, glabrous; segments unequal, the 

 3 outer broadly cuneate, undulate toothed at the truncate apex, 

 the 3 inner cuneate, much narrower than the outer : filaments 

 glabrous : achenes 3-angled. 



* Mem. Dept. Bot. Col. Coll. i : 1-180. 

 f BulL Torr. Club, 23 : 406-408. 



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