182 PROCEEDINGS OF THE AMERICAN ACADEMY 



the leaves half an inch in diameter, and the panicle rather simple. 

 Involucre a line long and about as broad, rather few-flowered. Pedicels 

 two or three lines long : perigonium as long, or at length longer. 



63. E. Watsonii, n. sp. Gracile ; foliis pra3cedentis srepius sub- 

 cordatis ; panicula decomposita patentissima laxe floribunda ; pedicel- 

 lis eglandulosis patenti-deflexis involucro angusto- vel clavato-campan- 

 ulato vix plurifloro 2-3-plo nunc paullo longioribus; bracteolis setaceis 

 parce glanduloso-barbellulatis ; perigonii albi vix rosei basi obtusi 

 segmentis conformibus ovalibus parum retusis, interioribus paullulum 

 minor ibus. — Nevada, in the Humboldt Mountains, Torrey. Star 

 Canon, W. Humboldt Mountains, alt. 5,000 feet, S. "Watson, in C. 

 King's Expedition. The exceedingly effuse panicle spreads in the 

 largest specimens over a foot in breadth. Pedicels much less deflexed 

 than in the next, the longest fully three lines long, and nearly thrice the 

 length of the involucre, but many of the later ones not longer than it, 

 that is, a line or a line and a quarter in length, either smooth or very 

 minutely and obscurely glandular. Perigonium a line long, or slightly 

 more when accrescent, narrower than in E. nutans, and not so very 

 broad at the base, but 6-parted, and not narrowed at base in the manner 

 of the next. 



64. E. cernuum, Nutt. PI. Gamb. p. 162. Gracile; foliis radi- 

 calibus (nunc in caule brevi) orbiculatis vel obovatis sublonge pe- 

 tiolatis floccoso-lanatis ; panicula effuso-decomposita saepius maxime 

 floribunda ; pedicellis mox deflexis lasvibus involucro campanulato 

 2 - 4-plo longioribus ; bracteolis setaceis brevibus subundis ; perigonii 

 albi vel subrosei 6-fidi basi turbinata acuta segmentis exterioribus 

 quadratis emarginatis retusis interiores oblonga dimidio angustiora 

 vix superantibus. — Plains of the Platte to New Mexico and Utah. 

 A span to a foot high ; the panicle in the larger plants very widely 

 spreading and floriferous. Involucre at most a line long. Flowers 

 barelv a line long when accrescent, often considerably less, smaller 

 than any others of this sub-section, and well distinguished from all 

 others of this section by the top-shaped base or tube, which is fully 

 half the length of the segments and tapers to the narrow insertion. 



Var. tenue : panicula graciliore minus florifera ; pedicellis capil- 

 laribus elongatis (3- 12 lin. longis), involucro minori vel tenuiori. — 

 Nevada and Utah; foot-hills of the Humboldt and Wasatch Mountains, 

 S. Watson, in Clarence King's Expedition. With just the flowers, 

 &c. of E. cernuum, — this differs remarkably in the filiform looser 



