DIPTEROUS FAMILY PANTOPHTHALMIDJE. 559 



every instance except one to be conspecific, and to be nymphs of 

 a species of Trachytes, which Mr. Hirst will describe in a forth- 

 coniing paper as new {cf. p. 565). In the single case forming the 

 exception, the pseudo-parasite was determined by Mr. Hirst as 

 an adult female of Macrocheles, sp, incert. {vide p. 588). It would 

 seem that these pseudo-parasites must infest the borings of the 

 larva), and attach themselves to the flies as the latter emerge 

 from the pupa-case, 



(h) S'l/stematic Portion. 



Taking into account synonymy already established, the total 

 number of species of Pantophthalmidfe at present recognized 

 amounts to twenty-four. In the following pages ten species, 

 previously described by various authors, are admitted as valid 

 and commented upon, notes being given on the specimens of 

 these species in the British Museum (Natural History), or other- 

 wise available to the writer for examination ; the names of nine 

 other species, hitherto accepted, are sunk- as synonyms; and six 

 species and one genus are described as new. As the result of 

 this paper, therefore, the number of known species of Pant- 

 ophthalraidpe, including those that the author has been unable 

 to examine, will stand at twenty-one. It is explained below that, 

 in agreement with Kertesz, and contrary to the course adopted 

 by Enderlein, the genus Paniophthahnus Thunb. is treated as 

 including Acanthomera Wied. In view of the limited amount 

 of material at the author's command, and since as yet both sexes 

 are known in the case of only a minoritj' of species, with much 

 regi'et no attempt has been made to construct a synoptic table. 

 Should the publication of the present paper fortunately result in 

 a considerable expansion of the National Collection of these 

 interesting Diptera, the construction of a reliable table of the 

 kind in question may eventually' be possible. 



Genus Pantoplithalmus Thunberg, 



Paniophthahnus Thunberg, Gotheborgs Kongl. Wettenskaps 

 ooh Witterhets Samhallets Nya Handlingar, iii. Delen, p. viii 

 (1819). 



Acanthomera Wiedemann, Diptera Exotica, Pars i. p. 60(1821). 



Megalomyia Bigot, Ann. Soc. Ent. France, 5" Ser., T. x.. Bull, 

 p. v (1880). 



Megalemyia Bigot, Ann. Soc. Ent. France, 6" Ser., T. i. p. 455 

 (1881). 



After due consideration, it has seemed better to follow Kertesz 

 (Cat. Dipt. iii. p. 294 (1908)), who gives the synonymy printed 

 above, rather than Enderlein (Zool. Anz., Bd. xli. p. 100 (1912)), 

 by whom Paviophthalmus Thunb. and Acanthomera Wied. are 

 treated as generically distinct. The course adopted by Kertesz 

 appeals the more reasonable one under the circumstances, in spite 



