Colorado Beetle. 87 



gardens are troubled with these animals is given in the Eeport on 

 p. 115. 



The small beetles also sent were Bathyscia wollastoid, an abundant 

 potato pest in East Kent (vide p. 84). 



Notes on the Colorado Beetle in England. 



The appearance of the Colorado Beetle in England in 1901 was 

 not surprising. Ships from American ports may very easily bring 

 over specimens that have flown on board whilst in harbour on the 

 other side. A single pregnant female woudd be enough to start a 

 colony. It is probably in this way that tlie colony established in 

 1901 in Tilbiuy Docks originated. It has been surmised that the pest 

 may have come over in American potatoes ; that is scarcely likely, for 

 the only American potatoes that are sent to this country are seed 

 potatoes, which are particularly clean. At present there is no infesta- 

 tion of the Colorado Beetle in Europe, so that it can only have been 

 derived from an American source. Two previous outbreaks have 

 been known in Europe, both in Germany. 



The outbreak of this beetle in 1901 was reported to the Board of 

 Agriculture during August. The beetles were then very vigorous, 

 •eggs and larvtB of all sizes being found. 



The colony was evidently well established, and looked as if it had 

 been in existence some little time. It was situated inside Tilbury 

 Dock on some potatoes on the workmen's allotments ; they extended 

 for about fifty yards, and had materially defoliated the potatoes in 

 some places. 



The adults did not readily seem to take wing, but crawled about 

 with great energy. Later on in the year, those taken away for 

 breeding pm-poses, however, showed a strong disposition to fly ; they 

 were constantly flying with great force in the breeding-cage in which 

 I kept them, and beautiful objects they are, too, when their brilliant 

 rose-coloured under wings are expanded. By keeping some specimens 

 in warmth, I succeeded in getting through a complete life-cycle by 

 •October, but those kept out-of-doors did not deposit any eggs after I 

 brought them away from Tilbury. 



The land where this beetle had taken up its abode was cleared of 

 all potato haulm, and the haulm burnt with paraffin at night on the 

 ground under the superintendence of the Board of Agriculture 

 officials ; the ground was also soaked with paraffin, ploughed ten 

 inches deep, and then dressed with gas lime at the rate of 60 tons 

 per acre. Potatoes were planted on and around parts of tlie area to 



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