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THE COLORADO BEETLE. 



Doryphora {Leptinotarsd) decern lineata. Say. 



From the regions of the Rocky Mountains the so-called 

 " potato bug," or " spearman," has spread over the greater 

 part of the North American continent. This rapid dispersal 

 during recent years has been mainly due to man's agency in 

 one way and another. Natural means of dispersal, however, 

 also seem to have aided its progress. 



Its great vitality under variable conditions in the beetle or 

 adult stage*, and the considerable time the beetles can live, 

 make this potato pest a source of danger to distant lands. 



Many insects have been introduced into foreign countries, 

 and have flourished and become serious pests. The Codling 

 Moth [Carpocapsa pomottella), the Mussel Scale [Mytilaspis 

 pomorum), and other fruit pests have been carried from 

 Europe to America, to Australia, to New Zealand, and have 

 become permanently established, and a serious source of loss 

 to growers. 



There is no reason why many North American pests should 

 not nourish just as well here as there. That the Colorado 

 Beetle can do so we have unfortunately had recent evidence. 

 During August its presence w T as reported to the Board of 

 Agriculture in some allotments in Tilbury Docks, in just such 

 a locality as one would expect to find a primary colony. 

 The beetles had been noticed for some time, and when seen 

 in August were breeding with great energy. Eggs, larvae in 

 all stages, and adults were found on a large patch of 

 potatoes. Although they were not then very plentiful, they 

 evidently had been, for the allotment holder stated that he 

 had been continually picking them from the potatoes for some 

 time. The inspectors who visited the plots also found large 

 numbers of the beetles and larvae. 



It has appeared in Germany on two occasions. There 

 drastic measures were employed, and the creature stamped 



* I have found that the larvae can also live for some time without food. One taken 

 from Tilbury is at present alive, having been without food for three weeks. 



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