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NOTES ON THE BEHAVIOR OF THE COLORADO POTATO BEETLE 

 IN GREAT BRITAIN. 



{Lcptinotdiisu [DoriipJiDia] ilecciiilineata Say). 

 By Feed. V. Theobald. 



Wye Court, Wye, England. 



The advent of the Colorado potato beetle into Great Britain in 

 1901 giwe rise to grave apprehensions, which, judgiiig from its behav- 

 ior during its stay on our shores, were certainly not unfounded. 

 For once the country was prepared to deal drastically with this 

 unwelcome intruder, for a bill had been passed by both Houses of 

 Parliament in 1877 by means of which the existing board of agricul- 

 ture has power to take over land infested Avith the Colorado potato 

 beetle so as to insure its eradication. The necessity of this measure 

 was amply shown during 1901 and 1902 when the " spearman " « was 

 present in this country. 



The few notes I made on the general behavior of this beetle during 

 its stay with us may not be unwelcome to those in whose land it 

 flourishes, and of interest to others into whose country it may any 

 day be imported. I believe the British invasion is only the third 

 that has occurred in Europe, the two j^revious outbreaks having 

 occurred in Germany some years ago. 



The beetle was reported to the officials at the board of agriculture 

 m August, 1901, as being present in some allotments in Tilbury 

 Dockyard. On the 22d of that month I visited the dockyard and 

 found the beetles very active and full of generative vitality. They 

 were not numerous, some two dozen or more only being observed, but 

 many more had evidently been at work and some had been collected 

 and killed. At this time they were depositing eggs, and I found 

 larvfv in all stages of development. At a glance one could see that 

 the beetles had been at work some time ; probably the colony had been 

 there some months before it was detected. The potatoes were 

 noticeably defoliated, but mainly, it seemed, by the larvae and not by 

 the adults. The beetles did not seem to take Aving, but were most 

 active, crawling about in the bright sunshine. I never saw^ one take 

 Aving in the open, but those I brought aAvay for further observation 

 became most active in the breeding cages, frequently using their rosy 

 Avings and dashing up against the glass of the cages. Later I noticed 

 them in my garden taking short flights under their muslin tents. 



The land Avhere this colony had taken up its abode Avas treated in 



a A name sometimes given to the Colorado potato beetle, based on tlie old 

 generic term Dorypliora. 



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