394 JOURNAL, BOMB A Y NATURAL HISTORY SOCIETY, Vol. XVIII. 



to 25 feet. A third soil consists almost entirely of sand and gravel ; 

 whereas a fourth kind, the so-called cotton-soil, is a black alluvial clay 

 which retains moisture for a long time, and has, besides, the power of 

 absorbing moisture from the atmosphere. 



It is to be regretted that Indian Botanists, on the whole, paid very 

 little attention to the relations which exist between the vegetation of 

 the various regions and its edaphic conditions. The consequence is 

 that we are not able, as yet, to say how the different soils influence 

 and modify physically and chemically the Floras of various areas in 

 the Tropics. Kurz 1 and Brandis 2 made a start in India, but theirs 

 are the only contributions in this direction as far as I know 3 . 



The climate of Coimbatore differs in many respects from that of 

 the neighbouring countries. Before we are going to describe it in 

 detail, we shall give a table showing the average rainfall in that part 

 of the District, which has been visited by Mr. Fischer. It is shown 

 on the map as lying north of the line drawn from near Mettapalayam 

 across the country to the boundary line between Madura and Trichino- 

 poli, including also a small part of the Nilgiris with the two elevations 

 marked as 4,000' and 5,000' {vide Plate A). 



Average Eainfall (1870 — 1903) in inches. 



1 S. Kurz: Preliminary report on the forest and other vegetation of Pegu, Calcutta, 1875. 

 cf. al=o : S. Kurz : Forest Flora of British Burma. 



2 D. Brandis : Die Familie der Dipterocarpaceen und ihre geographische Verbreitung. 

 Sitzungsbericht d. niederrhein, Gesellsch. fUr Natur-und Heilkunde zu Bonn, 1896. 



3 We mnst, of course, not forget the work done by the Agricultural Department by ex- 

 perimenting on and analysing the soils in many parts of India, and there is no doubt that it 

 will prove useful also for our purpose ; but it has, naturally, been carried on with special re- 

 ference to the agricultural products only, and the results have not been applied as yet to 

 the wild-growing plants. 



4 District Gazetteers, Coimbatore, Vol. II, 1905. 



