132 The Menace of Man's Dispersal of Insect Pests [April 16, 



black currant mite and the white fly of tomato. Elsewhere far more 

 destructive pests have been carried, such pests as Mexican boll 

 weevil, and pink boll worm of cotton, Colorado beetle, gipsy moth, 

 corn moth, fluted scale Hawaiian cane fly, San Jose scale and others ; 

 these are pests of the very first magnitude whose effects on crops amount 

 to millions sterling. The future menace is greater owing to (1) 

 increased railway communications provided by the Channel tunnel, 

 Gibraltar tunnel, the Cairo-Baghdad link (completed), and presently 

 the Basrah-Karachi, the India-Burma and Burma-China linking up'; 

 and (2) the aeroplane, which bridges sea routes at present only 

 covered by boats. The construction of aeroplanes and airships allows 

 them to carry insects : and whereas trains and boats start from 

 stations and docks in towns, remote from field and orchard, planes 

 and airships get up from fields and come down again in fields, t herd >y 

 directly transmitting the crop pest. 



Short cuts bridged by aircraft are : — Africa-Brazil ; Bombay- 

 Africa ; Peshawar-Turkestan ; Calcutta-Rangoon-Bangkok : Japan- 

 China ; Philippine Islands-Borneo- India ; Cairo-Baghdad-Karachi : 

 Java-Queensland ; Italy-Tripoli ; Florida-Cuba- Yucatan. 



In addition to carrying crop pests the aircraft will make possible 

 the rapid transmission of the tse-tse flies, mosquitoes with yellow 

 fever and malaria, lice with typhus, trench fever and relapsing fever ; 

 and this will be used as a war measure in future wars. Xot only 

 diseases, but virulent pests of crops, such as the bollworms, cane 

 borers, rubber, tea and coffee pests will be spread from one area to 

 another as an offensive measure. 



[H. M. L.] 



WEEKLY EVENING MEETING, 

 Friday, April 23, 1920. 



Sir James Crichton-Browne, M.D. LL.D. F.R.S., 



Treasurer and Vice-President, in the Chair. 



Sir Israel Gollaxcz. 

 Shakespeare's "Shylock" and Scott's "Isaac of York. 



[No Abstract.] 



