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ERISTALIS TENAX IN ENGLAND. 



BY A. G. BUTLER. 



In the May number of Entomologica Americana Dr. Ham- 

 ilton has an interesting article on the Pollenization of Chrysanthe- 

 mums by this fly, and he appears to think that it confines its atten- 

 tions to the flowers of these plants. In England Eristalis tenax is 

 more attracted by the large annual Sunflowers and double Marigolds 

 than by other flowers, but it certainly visits other flowers. Its re- 

 semblance to a honey-bee probably affords it a degree of protection, 

 as some birds are undoubtedly suspicious of it; but, as the Buntings, 

 including the American Nonpareil and Indigo-finch, the English 

 Robin, Nightingale and Missel-thrush, the White-eared Bulbul and 

 Leiothrix, seize and eat it without hesitation, there can be no doubt 

 that very many are destroyed by insectivorous birds. I grow Mari- 

 golds partly for the purpose of attracting these flies, which I turn 

 into my aviaries, and thus during September my birds get a con- 

 siderable amount of insect food, which they would otherwise have 

 to dispense with. 



Apropos to Dr. Hamilton's article in No. 5, of Ent. Amer., it 

 may be of interest to know that I took scores (and could have taken 

 hundreds) of specimens of Eristalis tenax on a patch of wild mus- 

 tard growing in this county some ten miles back from the lake last 

 September and October. I have speciniens in my cabinet that I 

 took in California in August. The fall flowers here on the prairie, 

 wild mustard, the different asters and golden rods, and the large 

 Composite; are always attractive to E. tenax, as I have noticed for 

 many years. O. S. Westcott. 



Additional Note. — It may be well to add that Eristalis tenax 

 has been quite common in New York State for years past, occurring 

 in early Spring, and more abundantly in the Fall, not only on 

 Chrysanthemums, but on nearly every species of flower, both culti- 

 vated and wild, in bloom at these seasons. On account of the 

 abundance of Compositae at the time of its occurrence the fly is most 

 often to be found on these flowers, but I am not inclined to believe 

 that it is in any manner restricted to this order of plants. I have 

 frequently noticed these flies flying about in the sun when the weather 

 was so chilly that no other living insect was to be found abroad. 



F. H. C. 



