iv TROPICAL FLORAS 79 



that the reckless clearing of large forest-areas, especially in 

 the tropics, produces devastation which can never be re- 

 paired. It leads to the denudation of the rich surface soil 

 by torrential rains ; this soil has been produced by countless 

 ages of forest growth, and it will require an equal lapse of 

 time to reproduce it. 



Returning now to the more direct teachings of small 

 areas when methodically studied, I may add that Dr. 

 Koorders has informed me that some years since he made 

 a visit to Minahassa, in N. Celebes, and in four months, 

 between the sea-level and 6500 feet, he collected or observed 

 about 2000 species of flowering plants, of which about 700 

 were forest trees. As these last are Dr. Koorders' special 

 study it is to be presumed he paid great attention to 

 them, yet he could hardly have obtained such a complete 

 knowledge of them in a few months as in the " reserves " 

 of Java, where, in successive years, not a single species 

 could have escaped discovery. This would imply that the 

 forest flora of North Celebes is even richer than that 

 of Java, and it is almost certainly more peculiar. And if 

 the larger islands of the Moluccas — Gilolo, Batchian, and 

 Ceram — are equally rich (and they have all the appearance 

 of being so), then every estimate yet made of the species- 

 population of the whole Archipelago must be very far below 

 the actual numbers. 



There must be hundreds of young botanists in Europe 

 and America who would be glad to go to collect, say for 

 three years, in any of these islands if their expenses were 

 paid. There would be work for fifty of them, and if they 

 were properly distributed over the islands from Sumatra to 

 New Guinea in places decided upon by a committee of 

 botanists who knew the country, with instructions to limit 

 their work to a small area which they could examine 

 thoroughly, to make forest trees their main object, but 

 obtain all other flowering plants they met with, a more 

 thorough and useful botanical exploration would be the 

 result than the labours of all other collectors in the same 

 area have accomplished, or are likely to accomplish, during 

 the next century. And if each of these collectors had a 

 moderate salary for another three years in order to describe 



