INl-liODUCTION. O 



exteuded back to the wing-base. Face, moiitli- 

 niaigin, and jowls Avithout strong bristles. 

 Thorax rareh' with a soft pubescence. Eyes of 

 the (S sometimes touching or approximated. 



Imagines always predaceous Microphona. 



Wings pointed at the tip ; venation abnormal, as 

 the 2nd and 3rd veins end close together almost 

 at the wing-tip ; no obvious cross-vein, and the 

 discal cell absent or reduced to a short middle 

 basal cell. Face with strong bristles round the 

 mouth -margin. Thorax with bristles but no 

 pubescence. Eyes widely and equally separated 

 in both sexes. Autenupe short and porrect, with 

 a long subdorsal arista. Colour always dull 

 yellowish, brownish, or greyish, but never green 

 or metallic Aceoptera. 



Verrall incorporates iu the above table the sixteen families of 

 Brachtcera which occur iu Britain, as well as the seven super- 

 families, which accounts for characters of miuor value often being 

 added, but it has seemed better to give his actual diagnoses of the 

 higher groups in full than to attempt to abbreviate them. One or 

 two terms in the venation and so on are changed for the purpose 

 of preserving uniformity with my previous volume. His table 

 (pp. 14 to 30) is illustrated witli typical figures and is a veritable 

 epitome of the salient characters of the Bkachycera. 



Coming to families, there has been less difference of opinion 

 amongst authors than as regards the higher groups, probably 

 because the characters are drawn solely from the perfect insects. 

 The exact rank of the Ccenomyid.e and Xylopiiagid.e as families 

 has been questioned, and the affinities of the LoNcnopTERiu.aE and 

 Phorid-E have given rise to considerable discussion. jN^otes on 

 these points will be found under the respective family headings. 

 I follow Osteu-Sacken and Verrall in placing the Xylomyin.e 

 subfamily of Xylophagid^ in the 1Stratiomyidj<;, and the remain- 

 ing subfamily, the Xylophagin.e, in the LEPTiDyE, to which 

 family also the C(enomyid,e are referred as a subfamily. 



Some authors have desired to remove the Myopin^ sttbfamily 

 from the Conopid.e to the Musctd.e and also to disband the 

 CEstbidtE altogether and spread the genera amongst the MusciDiE, 

 but with these views I cannot concur. 



Of two other families the taxonomic rank has been occasionally 

 disputed, the Acanthomerid.e and Apioceriu^e, but as neither 

 group occurs in the Orient they need not be discussed here. The 

 former family contains the most gigantic Hies known, so far as 

 bulk goes, measuring up to 40 milhmetres in length and 80 milli- 

 metres iu expanse of the wings, and they are confined to the 

 Neotropical llegion. They are allied to the Stratiomyid.e, 

 Leptid.e, and Tabakid.e. The ApioceridtE are akin to both the 

 Mtdaid^e and Asilid.e, Both these groups are now admitted to 

 be of family rank. 



