OF ARTS AND SCIENCES : JANUARY 26, 1870. 179 



zona, Thurber, Palmer, & Coues. A stouter and larger-flowered form 

 near San Antonio, New Mexico, Dr. Bigelow, in Whipple's Expedi- 

 tion. This species is to be distinguished from forms of the preceding 

 with leafy stem and erect branches of the panicle by the long and 

 delicate villosity of the bracteoles, and by the perigonium. The pan- 

 icle is ample, but the branches erect or strict. 



++++++++ Involucra saspius brevi-campanulata, parva, perigoniis 

 post anthesin auctis breviora, secus ramulos paniculaa nudae ple- 

 rumque intricatos sparsa, dentibus 4-5 latis rotundatis. Brac- 

 teolae in involucro paleolatre. Folia omnia subradicalia. 



56. E. Heermanni, Durand & Hilgard in Pacif. R. R. p. 14, 

 (Bot.) t. 17. Glaberrimum, vel forte glabratum, dichotomo-ramosissi- 

 mum ; involucris secus ramulos breves divaricatos paucis brevi-cam- 

 panulatis lineam longis latisque plurifloris bracteas ovato-subulatas 

 2 - 3-plo superantibus ; bracteolis glanduloso-ciliatis, exterioribus line- 

 aribus, intimis filiformibus ; perigoniis glabris, fructiferis lin. 2 longis, 

 segmentis exterioribus rotundatis interioribus oblongo-spathulatis multo 

 majoribus ; achenii rostro hirtello-scabro. E. genicidatum, Durand & 

 Hilgard in Jour. Acad. Philad. 3, p. 45, non Nutt. — California, Pose 

 Creek, Dr. Heermann. Sterile plains of Humboldt Co., Nevada, Tor- 

 rey. Old flowering branches only ; the base of the plant, leaves, and 

 root not collected. But the species cannot be mistaken. 



57. E. Plumatella, Durand & Hilgard, 1. c. t. 16. Floccoso- 

 lanatum, humile ; foliis radicalibus orbiculatis longe petiolatis subtus 

 albo-lanatis ; paniculae decompositae ramis rigidulis floribundis nunc 

 rectis nunc tortuosis demum implectentibus; involucro minimo campan- 

 ulato paucifloro bracteas baud excedente ; bracteolis filiformibus vix 

 barbellatis ; perigoniis albis et roseo-purpureis glabris lineam longis, 

 segmentis conformibus (interioribus paullulum angustioribus vix longi- 

 oribus) quasi panduriformibus ; achenio sursum hirtello-scabrido. — 

 Pose Creek, California, Heermann ; apparently a stouter form than 

 common. Nevada, chiefly in the desert, Anderson, Bloomer, Stretch, 

 Torrey, Watson. A span high, or rarely taller, from an annual root; the 

 panicles commonly forming implexed matted masses, their branchlets 

 usually slender and rather brittle. Segments of the perigonium 

 obovate-cuneiform and broadly refuse, when dry appearing panduriform 

 by the incurving of their margins about the middle. Embryo much 

 incurved, the cotyledons wholly accumbent. 



