282 [December, 



ON THE SPECIFIC IDENTITY OF ACLETOXENUS SYRPHOIDES, 

 Fbauenf., and G1TONA FORMOSA, Lw. 



BY J. E. COLLIN, F.E.S. 



Before writing my article upon Acletoxenus syrphoides, Frauenf .,* 

 which appeared in the January number of this Magazine for the 

 present year, I applied to the custodian of the collection of Diptera 

 at the Konigl. Zoologisches Museum at Berlin asking him kindly to 

 examine the type of Gitona formosa, Lw., and inform me whether it 

 possessed ocellar bristles, also to compare it with Frauenf eld's remarks 

 and illustrations in the Yerh. z.-b. Gres. Wien (1868), p. 899, that the 

 question whether Frauenfeld only redescribed Loew's species, or not, 

 might be positively settled ; I did not, however, receive an answer to 

 my enquiries, and had to publish my article leaving the question open. 



Since then I have heard from the present custodian, Herr Karl 

 Grimberg, to whom I am very grateful for the trouble he has taken, 

 explaining that owing to the death of his predecessor in office my 

 letter had been mislaid, and giving me the following answers to my 

 queries : — 



The type specimen of Gitona formosa, Lw., has no ocellar 



bristles. 

 The same differences exist between the venation of Gitona 



formosa and the other species of Gitona, as are represented by 



Frauenfeld's two illustrations. 



The venation of Gitona formosa agrees in every particular 



with the lower figure representing Acletoxenus, while the upper 



figure represents the typical venation of Gitona. 



It will thus be seen that the only paragraphs in Loew's descrip- 

 tion which made both Frauenfeld (in 1868) and myself (ante p. 3) 

 doubtful of the identity of G. formosa with A. syrphoides are proved 

 to be inaccurate, and without any hesitation I now sink Frauenfeld's 

 name as a synonym ; the species is undoubtedly generically distinct 

 from Gitona, and the references will now read as follows : — 



Acletoxenus fokmosus, Lw., Wien, Ent. Monatschr., viii (1864), 366 

 ( Gitona formosa) . 

 syrphoides, Frauenf., Verb. z.-b. Ges. Wien. xviii (1868), 

 152, 897; Collin, Ent. Mo. Mag. (2), xiii (1902), 

 1, pi. I. 



6, Harley Street, W. : 



November, 1902. 



* In this article I refer to the type of Agromyza omata, Mg. ; according to Becker (Zeitschr. 

 Hymen. Dipt., 1902, 340) this cannot now be traced. 



