Nortli American Entomologist 



Editor: A. R. GROTE. Tublishers: REINECKE & ZESCII. 



Buffalo Society of Natural Sciences. 500 Main Street, Buffalo, N.Y. 



Vol. 1. ]>XA.r5,CH, ISSO. INo. 1>. 



The probable Parthenogenesis of Cecidomyia destructor. 



By Dr. H. IIagex. 



I have been always puzzled to find that this insect, described as one 

 of the most obnoxious insects in the United >States is so very rarely 

 represented in collections. I have seen it in the collection of Asa 

 Fitch's types in Albany, and have only heard of two other collections 

 containing insufficient specimens in alcohol, so that, for the intended 

 publication of a plate, my old specimens, brought over from Europe, 

 had to be consulted by the engraver. In the twelve years which I 

 have passed in America I have given special attention to finding 

 the insect, but I was not able to ascertain a single case, where it 

 had been observed by others. Is it reall}' common and obnoxious 

 still, as it certainly was so many years ago ? I'erhaps my limited 

 correspondence is one reason that I hear nothing about it. 



I observed and raised the insect and its parasites in 1859, 

 in Jul}', in Koenigsberg, Prussia, and my specimens are now in the 

 biological Collection in Cambridge. As to their identity with C. 

 destructor there can be no doubt, as they. were compared by Mr. 

 Motschulsky with t3'pes from Mr. A. Fitch, presented to him by 

 Mr. A. Fitch himself during the travels of ,Mr. Motschulsky througli 

 the United States. The systematic collection in the Museum in 

 Cambridge contains no specimens, neither in Osten Sacken's nor in 

 Loew's collection and the Museum would be much indebted for a 

 good set of C. destructor from any quarter of the countrv, which 

 could not bo difficult to obtain, if indeed the insect is really so 

 common as it has been reported. I wish at the present time to 

 draw attention to an observation made by myself, which makes it 

 very probable that Cec. destructor is propagated, at least sometimes, 

 by Parthenogenesis. This kind of propagation would explain the 

 sometimes unexpectedly large numbei's of the insect; 



