xvi INTRODUCTION 



(1898), Lt.-Colonel Prain, Infrodtcction to Bengal Plants, p. 2 (1903), Sir 

 Joseph Baltou Hooker, A Sketch of the Flora of British India (1904).* In 

 this admirable paper Hooker divides British India primarily into three 

 Botanical areas, a Himalayan, an Eastern and a Western, the two last-named 

 being roughly separated by a line drawn meridional ly from the Himalaya to 

 the Bay of Bengal. These areas he divides into 9 provinces, 7 of which are 

 included in the present work, viz. : (1) The Eastern Himalaya, (2) The 

 Western Himalaya, (3) The Indus plain, (4) The Gangetic plain, (5) Malabar 

 in a very extended sense, (6) The Deccan in a very broad sense, (7) Ceylon, 

 (8) Burma, (9) the Malay Peninsula. 7 and 9 are not included here. In 

 stating the distribution of the species described in this book it was obviously 

 in most cases necessary to go into detail, and wherever feasible, the names of 

 the 64 subdivisions were used which had already been indicated in the intro- 

 duction to the Flora Indica of 1855, and which in his last sketch Hooker has 

 arranged tinder the 9 provinces now adopted by him. In many cases, 

 however, the distribution of species had to be further defiued, and here to a 

 great extent the administrative division of the Empire into districts and sub- 

 divisions has been used. It is assumed that those who may use this book are 

 familiar with the geography of India. In the case of a few of the less 

 common, but important species, I have added the locality aud the dates on 

 which they were found by me. It will I trust be understood that I had to 

 indicate the geographical distribution of a species in as few words as possible, 

 so that when a species is found in Chutia Nagpur and the Western Peninsula 

 it may be assumed also to occur in Orissa, though this is not specifically 

 stated. Again, when a species is found on the Khasi hills and in Chittagong, 

 it may be expected to occur also on the Lushai hills. The term Central India 

 is sometimes used in a wide sense, comprising the Central Provinces. 



The principal factors which influence the geographical distribution of trees 

 in India are latitude, elevation, moisture and the nature of the soil. In addition 

 to these, it must be borne in mind that there is a marked diiBference in the 

 vegetation of the Western and Eastern divisions of the country. The influence 

 of latitude and elevation above sea-level is obvious and is generally recognized ; 

 regarding the influence of soil, moisture and the difference between West and 

 East it may be useful to say a few words. Eegarding the influence of soil upon 

 forest growth in India, only a few isolated facts are known at present. Bal 

 forests are found on sandstone, conglomerate and on the sandy gravelly and 

 shingly soil of the Subhimalayan tract ; Eng {Dipterocarptcs tuhercidattis) 

 chiefly affects laterite ; Ilardiolckia hinata most commonly grows on sand- 

 stone, and if found on trap, as in South Berar, the rock is rich in veins 

 of quartz. Mimusops hexandra^ as far as known, behaves in the same 

 manner. Cupressus torulosa as a rule is only found on limestone. On the 

 other hand Teak thrives well on the sandstone and calcareous shales of the 

 Pegu Yoma, on gneiss, granite and other crystalline rocks east of the Sitang 

 river above Toungoo and in North Kanara, on trap in the Satpura range, and 

 in the Khandeish Dangs, on limestone in the Thaungyin forests of Tenasserim, 

 end it also grows on deep alluvial soil. The same may be said of many 

 important forest trees. Terminalia tomentosa^ it is true, and Diospyros 

 Melanoxylon thrive best on heavy clay soil, but we find them on different 

 geological formations. 



In Europe forest trees behave in a similar way. The Beech and the Silver 

 fir thrive best on calcareous soils, but they will grow on soils differing greatly 

 in regard to their physical and chemical constitution. The Larch in Switzer- 

 land and the Tyrol prefers crystalline rocks, which are poor in lime, while in 

 Bavaria and Salzburg this tree is commonly found on calcareous and not on 

 silicious soils. 



The trees and shrubs, which grow near the sea coast and on the banks of 



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A chapter in the forthcoming Imperial Gazetteer of India (advance copy). 



