PREFACE. XV 



with much useful information regarding the vegetation of those districts, 

 with which he was personally acquainted. In numerous cases they sup- 

 plied data concerning the geographical distribution of plants, which I 

 could not have obtained from any other source ; and I invariably con- 

 sulted them regarding vernacular names, the habit, mode of growth, and 

 products of the trees. Where I had no personal knowledge of the plant 

 as, for instance, GJiamcerops Ritchieana, Reptonia, Parrotia, and other 

 exclusively western trees I have for the general remarks mainly relied 

 on his manuscripts. For the trees and shrubs of those districts with 

 which he was not acquainted, the work has been based upon other sources 

 of information. "With regard to the Panjab, I could not have completed 

 this handbook without the assistance of Dr Stewart's manuscript, unless 

 I had returned to India and devoted several years to a botanical explora- 

 tion of the same ground where he had collected his information. 



I have utilised the materials collected by my late colleague as far as 

 they were embodied in his manuscripts, and in his various publications 

 and official reports. Many months have we spent together in the fierce 

 heat of the Kamaon Doons, in the Deodar forests of Kunawar near the 

 limits of arboreous vegetation, and in other districts of North-West India. 

 We have shared many a hard day's work, and have keenly discussed 

 many botanical questions. It is a melancholy satisfaction to me to record 

 the extent and value of his labours. Three new species were described 

 in Dr Stewart's manuscripts : Acer pentapomicum, Rhus punjdbensis, and 

 Adenantliera Oudhensis the two former discovered by him in the N.W. 

 Himalaya, and the third by Mr Eichard Thompson in the Oudh forests. 

 These species have been accepted by me as denned and named by him ; 

 and at the end of this volume, an analytical key to the chief arboreous 

 conifers of the N.W. Himalaya, by Dr Stewart, will also be found. Ee- 

 garding the limitation of certain species, I have formed views differing 

 considerably from those of Dr Stewart. This divergence of opinion 

 mainly relates to the following genera : Greicia, Zizyphus, Rhus, Acacia, 

 Embelia, Diospyros, Olea, Ehretia, and the Bamboos. I wished to have 

 placed the views Dr Stewart entertained regarding those species before 

 Indian botanists in his own words, but the state of his manuscripts pre- 

 vented the adoption of this course. They are, however, deposited in the 

 Library of the Eoyal Herbarium, Kew, and are available to those in- 

 terested in the arboreous vegetation of North India. 



A list of Dr Stewart's publications bearing on the subject of this book 

 will be found at p. xx. 



I have constantly consulted Jacquemont's Voyage dans l'lnde; 

 Hoffmeister's Travels ; Dr Hooker's admirable Himalayan Journals ; 

 Dr T. Thomson's clear and accurate description of the North- West Hima- 

 laya and its vegetation ; Madden's excellent papers on the Terai and outer 



