ON THE DIPTEROUS FAMILY PANTOPHTHALMID.E. 551 



30. A Revision oE the Family Pantophthalmid^ [Diptera], 

 witli Descriptions of New Species and a new Genus. 

 By Major E. E. Austen, D.S.O., F.Z.S. 



[Received May 29, 1923 : Read June 12, 1923.] 



(Text-iigures 1-11.) 



Table of Contents. 



Page 



(a) Iiitvoduction and Acknowledgments 551 



(h) JMbliograpliy 552 



{c) Geograpliical Distribution 552 



(d) Tnxononiic Position 553 



(e) Bodily Dimensions in PantopJitJialmida compared with 



tliose of Exceptionally Large Diptera belonging to 



other Families. — Giantism 554 



(/) Life-historj- and Bionomics 556 



(ff) Pseudo-Parasites 558 



(h) S^-stematic Portion 559 



(a) Introduction and Acknowledgments. 



In spite of, as compai'ed with the vast majority of Diptera, 

 imposing size and striking coloration — characters likely to attract 

 the attention of collectors in countries in which the flies forming 

 the subject of this paper ai-e found — Pantophthalmidre (formerly 

 known as Acanthomeridfe) are singularly rare in collections. It 

 is difficult to suggest even a possible reason for this, unless it is 

 to be found in the habits of the adult insects, which probably 

 spend most of their time in the dej)ths of Neotropical forests. 



At the present moment the series of these great Diptera in the 

 British Museum (Natural History), though doubtless the most 

 extensive in any collection in Europe, consists of only sixty 

 specimens. These, however, include no fewer than twenty-four 

 examples from the collection of the late M. J. M. F. Bigot, 

 which Mr. J. E. Oollin, F.E.S., has most generously presented to 

 tlie National Collection during the preparation of this paper. 

 The fact that among M. Bigot's series of specimens are the 

 types of five species, described by himself, Macquart or Bellardi, 

 renders this addition peculiarly valuable, and its timely acqui- 

 sition has enabled the writer in the course of subsequent pages 

 to elucidate for the first time a considerable amount of synonymy. 

 It is therefore a pleasant task hereby to express to Mr. Oollin, on 

 behalf of the Museum, sincere thanks for his public-spirited and 

 most welcome gift. 



Acknowledgments are also due to Professor E. B. Poulton, 

 F.R.S., F.Z.S., for the kind loan of the Pantophthalmid material. 



