OF ARTS AND SCIENCES : JUNE 11, 1867. 363 



Arnica parviflora : breviter pubescens, multicaulis ; foliis inae- 

 qualiter dentatis, inferioribus subcordatis longe petiolatis, superioribus 

 parvis saspe alternis stiblanceolatis spathulatisve in pe.tioluin margina- 

 tum angustatis, sensim in bracteis transeuntibus ; capitulis plurimis 

 paniculatis pro genere parvis ; ligulis nuUis ; aclieniis minutim glandu- 

 losis glabris. — Humboldt Co., in the northern part of California, in 

 thickets, Bolander. Rootstocks slender and branching. Stems a foot 

 high, slender. Radical and lower leaves 1 to 2 inches long, on petioles 

 of U to 3 inches in length. Heads 6 or 7 lines long, on rather slender 

 peduncles. Involucre slightly pubescent, of about 12 scales; the 

 flowers 20 to 30. Rays wanting in all the specimens. Achenia only 

 2 lines long. 



PsATHYROTKS ANNUA: Gray, PI. Wright. 2, p. 100, non PI. Thurb. 

 p. 323, &c. Mono Lake, Bolander. [Also on sterile saline plains, 

 Humboldt, Humboldt Co., Nevada, Dr. Torrey.] — Here, at length, we 

 have good and abundant specimens of Nuttall's plant, the Bulbostylis 

 {Psathyrotm) annua of PI. Gambel. ; with which, in the lack of suffi- 

 cient materials, I had confounded a related but distinct species. The 

 character of the genus moreover needing some correction, a revision is 

 offered in the appended note.* 



* PSATHYROTES, Gray, PI. Wright. 2, p. 100. 



Capjtulum homogamum, multiflorum. Involucrum circ. biseiiale ; squamis 

 disco subffiqualilius. Roceptaculum convexum vel planum, luidum. Corollae e 

 tuho proprio brcvissimo cylindricie, apico 5-dentatiB, deiitibus brevibus latis extus 

 villosis. Stamina prope basim corollas inserta : amherte elongatae, e caudatse, ia- 

 clusEe, demum semi-exsertse. Scyli rami compressi, capitellato-triincati vel obtusi. 

 Achenia turbinata vel oblonga, villosa. Pappus pilosiis, corolla brevior, setis 

 rigidulis infequalibus (vix sea levissime serrelalis). Herbte parvulte, depressas, 

 monocarpicje, subviscosae, odore balsamico graveoleutes ; foliis alternis dilatatis 

 petiolatis ; floribus luteis. 



§ 1. Ramosissimae, foliosse ; foliis Afriplicis facie longe petiolatis; capitulis alari- 

 bus et subcorymbosis breviter peduncutatis post anthesin nutantibus. Involucri 

 squamse 5 exteriores persistentes ; caeterse tenuiores, subscariosje, trinerves, cum 

 floribus 16-20 deciduae. Corollae angustas, apice lana longa implexa arachnoideae. 

 Styli rami breviusculi, apice subcapiteliato-truncati. Achenia villosissima, pilis 

 rigidiusculis summo apice plerisque (ut a Torreyo dicitur) bifidis. 



P. KAMOSissiM.\ : albo-tomentosa; foliis rotundatis parce crenatis ; involucri 

 squarais oblongis obtusis, 5 exterioribus latioribus obtusissimis ; floribus saturate 

 flavis ; acheniis breviter turbinatis ; pappi setis pluriserialibus valde intequalibus. 

 Tetradymia { Pulycli/mia) ramosissima, Torr. in Emory, Rep. (1848) p. 145. Psathy- 

 rofes annuu, Gray, in PI. Thurb. p. 323, & Mex. Bound. Surv. p. 102, quoad PI. 

 Thurb., Emoi'y, etc. 



