DISEASES AND PESTS 73 



that with sufficient care this can be done by means of 

 carbon bisulphide or hydrocyanic acid. Except in the 

 most expert hands, however, neither of these can be 

 used without some danger to the tree, and both are 

 dangerous in the hands of careless persons. Neither 

 can be advised for general plantation use. The use of 

 salt, and of sand and ashes, or best of all of very finely 

 ground glass, any of them sifted among the leaf-bases 

 of the crown of the tree, has been recommended as a 

 means of keeping the beetles from going into individual 

 trees. The immunity which can be provided in this 

 way probably rests upon the irritation of the beetle by 

 particles which get between the segments of its body 

 and cut into him ; but this immunity is at best only 

 partial. Either poison or this method may sometimes 

 be used to good purpose in protecting individual trees 

 which are especially valuable, as, for instance, where 

 they are used for decorations on lawns; but on a 

 plantation scale it has not been shown that the use 

 of the ashes or other fine particles produces a sufficient 

 freedom from attack to make it worth practising. 



Since the completion of this manuscript, three papers 

 have arrived, dealing with the presence of Oryctes 

 rhinoceros in Samoa. The most comprehensive of 

 these, being in the nature of a review, is in the Gardens' 

 Bulletin of the Botanic Gardens at Singapore for 

 December 1913. A very full account of the work is 

 also given by Friederichs in Der Tropenpjlanzer, 17 

 (1913), 538. The beetle is supposed to have reached 

 Samoa in 1910, or possibly in 1909, in a shipment of 

 rubber stumps from Ceylon. It was first noticed, 

 November 4, 1910, in coco -nuts near the Customs 

 House at Apia. 



Quoting from the Singapore publication, by Burkill : 



On the 8th of November 1910, the Government of Samoa 

 issued a proclamation in vernacular to the effect that the beetles 

 and their grubs should be collected, and promising a reward of 



