122 THE CANADIAN ENTOMOLOGIST. 



Dr. Gustav Mayr, of Vienna, in a letter just received, states that Dr. 

 Adler, of Schleswig, has this year pubhshed an " epoch-marking " paper 

 upon the subject of agamous reproduction among the Cynipidfe.''' 



Dr. Adler finds that what have been described as fourteen distinct 

 species of Cynipidse — belonging to six distinct genera — are really but 

 seven species. 



Four species of Neuroterons are found to be the agamous forms of 

 as many species of Spathegaster. 



Two species of Aphilothrix are the agamous forms of two species of 

 Andriais, and a species of Dryop/ia?ita is the agamous form of a 

 Trigonaspis. 



Dr. Mayr himself was at work upon this problem, but had not suc- 

 ceeded, as his efforts to grow oak trees in his garden had failed. He had 

 not given up the attempt, but had ordered more trees to plant this spring. 



Neither Dr. Mayr nor Dr. Adler seem to have seen my article. I 

 communicated the substance of it in a letter to Prof. Albert Miiller, then 

 in London. This was read before the London Entomological Society at 

 the meethig of April 7th, 1873, but I notice that English Entomologists 

 continue to talk about Hartig's experiments, and agamous reproduction 

 through an infinity of generations, and of a hypothetical male gall fly that 

 must appear now and then, always just in time to save the race from 

 extinction. 



Dr. Adler's paper will no doubt receive the attention it justly deserves 

 and it is to be hoped that the success that has followed his experiments 

 may lead others to aid in developing the history of this singular family 

 of insects. 



It is not safe to assume that the history of one species will be the 

 history of all, but the idea that these insects are perpetuated through 

 many generations by unimpregnated females must be abandoned. 



* Since the above was written I have received a copy of Dr. Adler's paper ; also a 

 letter in which he kindly consents to the publication of all or a part of the paper. I 

 propose shortly to prepare for publication in the Entomologist a summary of his 

 remarkable discoveries. 



