987 



988 



tinct species, 



. 



W. LINGUiATA Ab 

 W. 



79 



T cl b 



g 



Bth 



' 



Genus WYETHIA Nnttall. 



Am phil 



X: CAIiIPOBNICUM Greene, Man 171. 



XEROBOTRYS Nutt, Am phil sc tr ns, 



8:267 (1843). = Arctostaphylos fide IK. 



X. ARGUTUS Nutt, lc, 268. B 1:453 as A: 



tomentosus. 



X. CORDIFOLIUS Nutt, lc. B 1:453 as 



A: tomentosus. 



X. TOMENTOSUS Nutt, lc, 267. B 1: 



X. VENULOSUS Nutt, Bth 321. B 1: 



453 as A: pungens. 



XEBOPHYLLUM Michx Fl 1:210 (1803). 



X. DOTTGLASn Wat 14:284. B 2:186 

 26:378 X. SETIFOLIUM Michx, Fl 1:211. (B 2: 



185 as tenax as to Lindl, bot reg t 1613, 

 280 (1894). not Michx.) 



X. TENAX Nutt, Gen 1:235. B 2:185. Par 



53. setifolium fide IK. 



XIMENESIA Cav, Ic 2:60 t 178 (1793). 

 - Verbesina fide IK. 



X. ENCELIOIDES Cav Ic 2:60 t 178 ; B 



TJ- n 7^-r-r 1-350 as Verbesina e. T & G Fl 2:359. 



Heller Cat 7 (1898). M 1:5 XYLOCOCCUS Nutt, Am phil sc tr, ns, 



8-258 (1843). Arctostaphylos fide IK. 



X. BICOLOR Nutt, lc, 259. B 1:454 as 



XYIiOBBHIZA Nutt, Am phil sc tr, ns, 

 7:297 (1841). = Aster fide IK. 

 X. PBUTESw!NS P 3:48. 

 X. GIiABBIUSCUIiA P 3:47. 

 XYLORRHIZA ORCUTTII Green* 



Greene pitt 3:48, based on Aster orcuttii 

 A 1:58 f<*r. 

 X. PABBYI P 3:47. 

 XYLORRHIZA TORTIFOLIA Greene. 

 P 3:48. A 1:5 8d. 

 ~. VENUSTA M 1:8. 

 X. VILLOSA P 3:47. Parry, PI Wyo 4, 

 X. WBIGHTH P 3:47. 

 Genus XYI.OTHEBMIA Greene. 

 See Pickeringia for description. 

 X. MONTANA Greene, based on Picker- 

 ingia m. Par 236 t. Ab 206. 



Genus YUCCA Linnaeus. 



YUCCA ALOIFOLIA Linn. 



Y. ANGUSTIPOLIA Pursh, Fl 1:227. Br, 



YUCCA ARBORESCENS Trelease. 



Ab 92. Joshua tree. Mohave. 



Y. ALOIFOLIA L, sp pi 319 (B 2:164 as 



Whipplei as to T. Pac Ry R 4:147.) 



Y. ANGUSTIPOLIA Pursh, Fl 1:227. Br, 



Colo 244, 246, = Glauca fide IK. 



Y. BACCATA T, Mex bound 221. Br, 



Colo 228, 229, 244. B 2:164. (Cal pi = 



Mohavensis.) 



Y BREVIFOLIA E, ex Wat, bot king 



496. B 2:164. Da 17. See arborescens. 



See Clistnyucca arborescens. 

 Y. DRACONIS L, Amoen ac 3:407. 

 n Dracaena draco fide IK. 

 Variety ABBOBESCENS T. Pac Ry R 

 4-147. ':= brevifolia fide B 2:164. 

 Y. PII.AMENTOSA L, sp pi 310. B 2: 

 165. 

 YUCCA GLORIOSA L. 



Stem from a few inches to 6 feet high, 4- 

 6 indies in diameter, usually simple, cov- 

 ered with a shaggy coat of old withered 

 pendant leaves; leaves about 2 feet long, 

 IV* to 2% inches wide, stiff, sharply pun- 

 gent; panicles 2-4 feet long, 1-1% in diam- 

 eter. North Carolina to Florida, on sandy 

 sea beaches. 

 Y. GRAMINIFOLIA Wood, Phil ac pr 



P1 



- Am >"' sc tr 



XAMACBISTA P 4:26. 



Genus XANTHIUM Tournefort. 



X. ACUTTJM P 4-62 



X. AFPINE P 4:60. 



X. CAJ.IPOBNICTTM P 4 '62 



X. CAMPESTBE P 4'61 



X. CAN-ADENSE Mill, Diet ed 8. Greene, 



1:58. P 2 4 : :59 2 6^2 adventive ' Ab 414 ' 



X. GI-ANDULIPEIfcUM P 4:61. 



X. 3VL/LCROCAH.PUM P 4:59 



X. OBIEITTALE P 4 '58 



X. PALUSTBE P 4:63. 



X. SliPHUPOLIUM P 4:60. 



pi 98? - B i:M - Ab 



XANTHIUM STRUMARIUM Linn. 

 L, sp pi 2:987 (1753). McClatchie, Er 

 2:125 Cat. Br, Colo 231. Cov 4:130 Char- 

 leston mts. B 1:346. 



Type locality: "in Europe, Canada, Vir- 

 ginia, Jamaica, Zeylona, Japonia." 

 X. VARIANTS P 4:59. 

 XANTHOCEPHAI.T7M Willd. 



