330 PROCEEDINGS OF THE AMERICAN ACADEMY. 



single, terminal, short-peduncled, less frequently 3-4, corymbose, in- 

 cluding the rays 1^-1^ inches in diameter: involucre of few subequal 

 lance-linear attenuate finely pubescent and ciliolated scales ; the latter 

 loosely imbricated in 2-3 series, rather firm and broadly white-mar- 

 gined near the base, 4 lines long ; the very acute tips often purplish : 

 rays 12-18, white or pink, 6 lines in length, \\ lines in breadth, 

 3-toothed at the apex ; disk flowers including the silky achenes 5 lines 

 in length : pappus rather copious, of unequal bristles but not distinctly 

 double. — A. Engelmanni, Gray, var. (?) paucicapitatus, Robinson, 

 Proc. Am. Acad. xxvi. 176. — Collected by C. V. Piper in the 

 Olympic Mountains, Washington, August and September, 1890 (nos. 

 926, 934). Never satisfied with the earlier and somewhat provisional 

 disposition of this plant, I have returned to its study, and conclude 

 that it is specifically distinct from A. Engelmanni, through its much 

 less imbricated involucre of subequal scales. It should stand in the 

 genus near A. Xylorhiza, Torr. & Gray. 



Dioscorea Dugesii. Stem slender, climbing, angulate, sparingly 

 pubescent with fine brown hairs : leaves ovate, cordate, sharply acumi- 

 nate, thin, 9-nerved, pellucid-lineolate, nearly or quite smooth, 2^ inches 

 long, 2 inches broad; petioles pubescent, 1^ inches loug : staminate 

 flowers 1|- lines in diameter, borne in short slender simple solitary 

 axillary pubescent racemes 1^—2 inches in length: peduncles but 2 

 lines long ; pedicels scattered, ^ line in length, 1-3-flowered : bracts 

 subulate, considerably exceeding the pedicels : segments of the perianth 

 linear-oblong or linear-lanceolate, obtuse, with crisped margins : sta- 

 mens six, equal, inserted on the perianth near its base, half as long 

 as the segments. (Fertile plant not seen.) — Collected by Prof. Alfred 

 Duges at Guanajuato, 1880 (no. 37). A slender species, somewhat 

 resembling D. remotiflora, Kunth. 



