MYDAIDJE.. 315 



which are often hidden ; ovipositor produced but never elongate, 

 with or without a terminal circlet of spines. 



Leys strong and stout, of moderate length ; anterior pairs some- 

 times smaller; hind femora normally slightly thickened, nearly 

 always serrate or spinose below ; tibia? often with a row of small 

 spines on either the middle or hind pair only, or on all three 

 pairs ; apical tibial spines absent or sometimes present on all 

 three pairs ; hind tibiae generally with a strong apical spur or 

 two or three bristly spines ; tarsi devoid of all but the very small 

 close-set bristles on underside ; pulvilli two, moderately large, 

 empodium absent, claws long. 



Wings witli a very characteristic venation. Auxiliary vein 

 long; 1st longitudinal vein very long, ending at some little dis- 

 tance from wing-tip ; prrefurca very short, generally extremely 

 so, starting at about one-third of the wing, distinctly before the 

 discal cell ; 2nd longitudinal vein always ending in the 1st towards, 

 but not close to, its tip ; 3rd longitudinal vein starting very near 

 base of 2nd, always forked at beyond half its length, the branches 

 long, generally curved, and more or less parallel ; upper branch 

 ending in the 1st longitudinal just beyond tip of 2nd vein ; lower 

 branch ending either at the tip of the 1st vein or in costa just 

 beyond ; anterior cross-vein present, short or very short,* placed 

 much beyond middle of wing, towards tip of discal cell ; 4th longi- 

 tudinal vein with both branches either simple or forked, prongs 

 of either branch or of both branches sometimes recurrent ; t 

 normally the anterior prong of the upper branch curves upward 

 and ends in the costa well before the wing-tip, sometimes ending 

 at the tip of the 1st vein. In one (non-Oriental) genus (Mitro- 

 detus), both branches of the 4th vein curve upwards and end in 

 the 1st vein, but this is exceptional. Posterior prong of upper 

 branch generally recurrent or nearly so ; normally the lower 

 branch of the 4th vein ends in the upper branch, often (as in 

 Mydas) recurrent and united to the apical portion of the upper 

 branch of the 5th vein. Discal cell always present, elongate, 

 often irregularly or even fantastically shaped ( Mitrodetus) ; pos- 

 terior cross-vein normally situated. The 5th vein forks widely, 

 the upper branch never forming any part of the discal cell, 

 generally curving upwards, joining the lower branch of the 4th 

 vein, or it may be considered to anastomose with the apical part 

 of that vein, thence running jointly with it to the margin ; J 

 lower branch of 5th vein ending in 6th (anal) vein near its tip ; 



* Practically, or perhaps actually, absent in only one genus, Megascelus, 

 which is not Oriental. 



t My reading of the branches of the 4th vein differs from that of Verrall, in 

 which the discat cell is said to emit two or three veinlets. 



+ However, Verrall distinctly says " never running clear to the wing-margin, 

 but always causing a long, closed, normally 4th posterior cell to he under and 

 parallel witli the discal cell. ' The presence of the closed 4th posterior cell 

 referred to does not alter the position, and the vein that runs from the junction 

 of the 4th and f>th veins to the wing-margin may be regarded as the continua- 

 tion of either one of them or of the two united. 



