488 



INDEX. 



Viola latistipula, Hemsl., 324. 



pubescens, 324. 

 Vitis a!t.tivulis, Michx., 337. 



cordifolia, Michx., 337. 



incisa, Nutt., 337. 



w. 



Wedge photometer, the, 231. 

 White tourmaline, 57. 



X. 



Xanthoxylum Clava-Herculis, Linn., 

 335. 



macrophyllum, Nutt., 335. 



rterota, HBK., 335. 

 Xylopleurum, Sx^ach, 356. 



Zizyphus lycioides, Gray, 336. 



obtusifolius. Gray, 336. 

 Zornia diphylla, Pers., 344. 



tetraphylla, Michx., 344. 



University Press : Jolin Wilson and Son, Cambridge. 



