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XIX. On a visit to Ceylon, and the relation of Cei/lonese 

 beetles to the vegetation there. By George Lewis. 



[Read August 2nd, 1882.] 



In Ceylon the usual outlines of an island divide the 

 country into natural areas, each one of which is distinctly 

 different from another in soil and climate, and con- 

 sequently in fauna and flora. And if we consider roughly 

 what these features are, we shall understand something 

 of the general characteristics of the insects and their 

 relation to the varying physical conditions under which 

 they live. • The differences which are sufficient for this 

 note are primarily traceable to the formation of the earth's 

 surface, and are easily divided into three sections : — 



1. The hot plains, or low lands of the coast, with 

 rivers. 



2. The intermediate altitudes, with fair-sized streams. 



3. The higher altitudes, with elevated plateaux and 

 mountain torrents and rivulets. 



Ceylon from very remote times has been almost en- 

 tirely, if not quite, covered with dense jungle, and as the 

 soil is an extremely poor one, for the best elements of it 

 are carried away by the heavy rains, the vegetation which 

 has arisen has naturally largely derived its nutriment 

 from the moisture in the atmosphere. This is true of 

 the hard- wooded timber which forms the mass of the 

 jungle, and even more dependent on the general humidity 

 are the ferns, orchids, and other parasitic plants which 

 grow upon and often cover the trees. If the south-east 

 monsoon ceased to bring the abundant rain to Ceylon, 

 the island would become a useless desert ; the rain alone 

 keeps it verdant, as we see it, and in the north about 

 Hambantota, where the rainfall is only 34 in., there is 

 hardly any verdure on the sandy plains. The district 

 about Colombo, where the vegetation is rich and tropical 

 in every sense of the word, is entirely of a sandy soil, 

 and there is little in it to support the beautiful and strange 

 vegetation growing there, and the secret of the luxuriance 



TRANS. ENT. SOC. 1882. PART III. (SEPT.) 3 Q 



