OF ARTS AND SCIENCES. 59 



CichoriacecB. 



Stephanomeria, Nutt. A revision of the genus for the Flora of 

 North America results in some increase of the species, and a better 



I- Involucrura laxiusculura, pauciseriale, bracteis tenuibus angustis acutissimis 

 vel acutatis saepissiiue puberulo-granulosis, 



*+ Apice subito breviter mucrouato-acutatis : capitula 10-15-flora, laxe cymoso- 



paniculata. 



P. MiCROCEPHALA, Gray, PI. Wright, i. 127, & Bot. Calif, i. 422. Acourlia 

 microcepliala, DC. S. W. California. 



•w •«• Sensim acutissimis: capitula laxe vel aperte cymoso- vel thyrsoideo- 



paniculata. 



= Folia basi lata cordiforrai vel auriculata pi. ni. amplexicaulia, cum ramis 

 ininuta puberula vel granulosa, nunc viscidula. 



P. Thurberi, Gray, PI. Thurb. 324. Capitula 5-6-flora. S. Arizona, Thurber, 

 Lemmon. 



P. oxTLEPis, Gray, Proc. Am. Acad. xv. 41. Capitula 12-16-flora. {Acourtia, 

 Scluillz Bip. in coll. Liebm.) 



P. iiEBECLADA, Gray, PI. Wright. 1. c. Acourtia hebeclada, DC. Prodr. vii. GG; 

 Deless. Ic. Sel. iv. t. 95. Capitula 15-20-flora. 



P. Humboldtii, Gray, 1. c, must bo a factitious species. One element, which 

 gives the name, is Dume.riUa IJuinboldtii, Less, in Linnasa, v. 1-3, described from 

 an imperfect specimen of Humboldt's in the Willdenovian herbarium, the num- 

 ber of flowers in tiie head not mentioned, but the involucral bracts described as 

 broad and rather obtuse or acute. In Syn. Comp. 408, Lessing refers to this 

 Proustia Mexicana, Don. DeCandolle follows tliis, making the character simply 

 "capitulis 5-floris." This is taken from Don, who describes an evidently differ- 

 ent plant, with "involucri squamis ovato-lanceolatis acuminatis." Don's plant, 

 from the collection of Mor-ino and Sesse (which was largely from the north), 

 answers not badly to P. Thurberi, of which the outermost involucral bracts are 

 "ovato-lanceolatis acuminatis." Lessing's plant, which would carry the name 

 llumboldlii, may be P. reticulata. 



= = Folia crassiora basi angustiora, baud amplexicaulia, cum ramis glaber- 



rima, subglauca. 



P. Seemanni, Gray, PI. Wright, i. 127. Capitula laxe cymosa, 8-10-flora. 

 -»- -t- Involucrum laxiusculum, pauci-pluriseriale ; bracteis tenui-chartaceis ob- 



tusis vel obtusiusculis (nunc mucronato-acutatis), dorso laevi glabro : folia 



submembranacea vel chartacea, nee coriacea, 



■*-<• Lanceolata, basi angusta nee auriculata, venis parum reticulatis. 



P. CoTJLTERi, Gray, Proc. Am. Acad. xv. 40, pro parte. Caule vel ramo gracili 

 apice nudo aperte cyraoso-polycephalo : foliis bipoUicaribus lato-lanceolatis 

 parum denticulatis (infimis baud visis) ; capitulis (parum seniipollicaribus) 7-8- 

 floris fere omnibus pedicellatis ; involucro pauciseriali, bracteis lineari-lanceolatis 

 (semilineam latis) obtusiusculis. — Mexico, near Zimapan, Coulter, no. 234. — 1 

 had confounded it with a Mexican form of the next. 



