Willow, 752 



arroyo-, 764 



beaked-, 765 



black-, 757 



family, 737 



fire-, 766 



gray sandbar-, 761 



-herb, 1190 



long-pedicelled-, 760 



narrow-leaved prairie-, 

 766 



-oak, 786 



peach-leaf-, 759 



primrose, 1178 



red-, 760 



sandbar-, 763 



silvery desert-, 761 



-smartweed, 823 



southwestern black-, 759 



stinking-, 1055 



water-, 1157 



yellow-, 759, 764 



yew-leaf, 761 

 Wind-bags, 573 

 Winter 



-berry, 1098. 1099 



-cress, 981 



American-, 981 



-grap>e, 1111 

 Wire rush, 610 

 Wiregrass, 816 



muhly-, 249 



Persian-, 814 

 Wislizenia, 987. 989 



refracta, 989 

 Witch-hazel family, 1011 

 Witches" shoelaces, 1360 

 Witchgrass, 323 

 Withe-rod, 1556 

 Woe-vine, 962 

 Wolffia. 3. 4, 573 



Columbiana, 575 



papulifera, 575 



punctata, 575 

 Wolffiella. 564. 575 



floridana. 578 



gladiata, 578 



lingulata, 4, 578 

 Wolfs trisetum, 220 

 Wood 



-betony, 1499 



-nettle, 791 



-sage, 1408 

 Woodreed, 234 



stout-, 234 

 Woodrush, 645 

 Woodwardia, 65 



angustifolia, 67 



areolata, 67 



virginica, 65 

 Woolly 



-blue violet, 1153 



-rose-mallow, 1121 



-sedge, 544 

 Wormseed, 854 

 Wormwood. 1689 



Xanthium, 1365 1586, 

 1646 



cenchroides, 1646 



chinense, 1646 



italicum, 1646 



orientale, 1646 



pensylvaniciim, 1646 



saccharatum, 1646 



speciosum, 1646 



spinosum, 1646 



strumarium, 1646 

 Xanthocephalum, 1608 



gymnospermoides, 1608 

 Xanthorhiza, 915 



simplicissima, 915 

 Ximenesia 



australis, 1660 



encelioides, 1660 

 cana, 1660 



exauriculata, 1660 

 Xylorhiza, 1609 

 Xyridaceae, 578 

 Xyris, 580 



ambigua, 581 



arenicola, 583 



Baldwiniana, 581 

 tenuifolia. 581 



caroliniana, 583 



difformis, 587 

 Curtissii, 588 

 difformis, 588 



elata, 588 



Elliottii, 581 



flexuosa, 583 



iridifolia, 585 



Jupicai, 587 



platylepis, 583 



tenuifolia, 581 



torta, 583, 585 

 occidentalis. 585 

 Yarrow, common-. 1686 

 Yaupon, 5, 1101 

 Yeatesia. 1528 



viridiflora, 1528 

 Yellow 



-bee-plant. 988 



-cow-lily, 906 



-cress, 971 



-dock, 802, 805 



-eyed grass, 580 

 family, 578 



-flag, 679 



-floating-heart, 1331 



-foxtail, 334 



-fringed orchid. 5, 697 



-fringeless orchid, 700 



-jessamine, 1311 



-lotus, 912 



-nut-grass, 456 



-puff, 1043 



-rocket, 981 



-star-grass, 5, 660, 667 



-sunny-bell, 655 



-sweet clover, 1047 



-thistle, 1695 



-trumpet, 990 



-violet, smooth-, 1152 



-water crowfoot, 953 



-water lily, 3, 902 



-willow, 764 



-willow tree. 759 



-wood, 1301 

 Yellowroot, 915 

 Yerba de tago, 1646 

 Yerba mansa, 737 

 Yew-leaf willow, 761 



Zannichellia, 6, 9, 10, 117 



palustris. 117 

 Zannichelliaceae, 117 

 Zephyr-lily, 669 

 Zephyranthes, 669 



brazosensis, 669 



Candida, 669 



chrysantha, 669 



Herbertia, 669 



pulchella, 669, 671 



refugiensis, 671 



texana, 671 

 Zerna Richardsonii, \11 

 Zexmenia hispidula, 1660 

 Zigadenus, 650 



densus, 653 



elegans, 650 



glaberrimus, 653 



leimanthoides, 653 



porrifolius, 653 



virescens, 653 

 Zizania, 277 



aquatica, 277 

 angustifolia, 280 



texana, 277 

 Zizaniopsis, 280 



miliacea, 280 

 Zizia, 1230 



aptera, 1230 



aurea. 1230 

 ZostereUa 



dubia, 604 



longituba, 604 



■fr u. 



GOVERNMENT PRINTING OFFICE; 1972 O 450-827 



1777 



