.win TREFACE. 



daceae, Haloragacese, Amaryllidacese, Iridacese, Typhacese, Araceae, 

 and Cucurbitaceae. The principles kept in view in effecting those 

 changes have been also observed throughout the present work, so 

 that standard English names for Classes and Orders are now no 

 longer wanting. The Author confidently believes that every intel- 

 ligent reader will admit that such names as Urn-mosses, Taccads, 

 False Hemps, Pepperworts, Bristleworts, Chenopods, Hydrocha- 

 rads, Scale-mosses, Birthworts, and Fringe-Myrtles are preferable to 

 Bry-a-ce-ae, Tac-ca-ce-ae, Da-tis-ca-ce-ae, El-a-ti-na-ce-ae, Che-no- 

 po-di-a-ce-ae, Des-vaux-i-a-ce-ae, Hy-dro-cha-ri-da-ce-ae, Jun-ger- 

 man-ni-a-ce-ae, A-ris-to-lo-chi-a-ce-ae, Cha-mae-lau-ci-a-ce-re, and 

 other sesquipedalian expressions. 



University College, London. 

 October, 1845. 



Note to the Third Edition. — In the present Edition the 

 reader will find much new matter, and a considerable number of 

 new woodcuts. Many of the former illustrations have been 

 replaced by better ones. The lists of genera have been completed 

 up to the day on which each sheet was sent to press, as far as the 

 materials at the command of the author permitted, and the whole 

 of such additions have been indexed. Few changes have been 

 made in the computed number of genera and species under each 

 natural order, because, in the present very unsatisfactory' state of 

 systematical Botany, when a writer of no mean station con- 

 verts one true species into three false genera and twenty false 

 species, it seems hopeless to arrive at a much nearer approach to 

 the truth than was attained in 1845. Many kind friends 

 have again assisted the author in his task, and his most 

 grateful general thanks are due to them, in addition to those 

 separate acknowledgments which appear wherever new matter 

 has been contributed. 



July 21, l :;:.;'.. 



