AUSTRO-MALAYAN DIPTERA 485 



is required to discern it ; the third vein likewise runs alongside 

 of the second and diverges only towards its end ; thus the sub- 

 marginal cell, linear in its proximal portion, becomes trumpet- 

 shaped towards the end. The anterior crossvein is unusually 

 long (as long as the posterior one), which gives an extraordi- 

 nary breadth to the first basal and first posterior cells ; the 

 latter thus appears rather short, and out of shape. The pecuhar 

 shape of the discal cell is due to the position of the anterior 

 crossvein , very near its end ; to the curvature of the fourth 

 vein, enlarging the first basal cell at the expense of the discal, 

 but, more than all, to the very oblique course of the posterior 

 crossvein, which appears hke a prolongation of the fifth vein , 

 and reduces the second posterior cell to a narrow stripe along 

 the margin of the wing. The third posterior cell is likewise 

 narrow, as well as the axillary. The anal cell resembles that 

 of Phytalmia, it is small, and drawn out in a short point. The 

 male of D. brevicornis, as represented in the Tr. Ent. Soc. 1. c. 

 fig. 2 shows , with shght modifications in degree , exactly the 

 same characters. 



In the females, the same characteristics exist, only in a lesser 

 degree. The costa is not angularly bent , and thus the wing 

 has the normal shape ; the distance between the tips of the 

 auxiliary and of the first vein is very considerable still and the 

 costal cell rather broad (much narrower in D. ophion than in 

 D. myrmex) ; the close approximation of the first , second and 

 third veins is the same, (the third vein is a little more distant 

 in D. myrmex than in D. ophion) ; the length of -the anterior 

 crossvein , the curvature of the antepenultimate section of the 

 fourth vein, and the other parts of the venation are the same 

 as in the male ; the posterior crossvein is somewhat less oblique. 



The affinity to Phylalmia appears especially in the structure 

 of the parts of the head and of the abdomen. The eyes are 

 less rounded , more oval , than in Phytalmia ; the cheeks less 

 broad. The part of the cheek, under the eye, which in Phytal- 

 mia o^ bears the hornlike processes, and in the 9 is marked 

 by a ridge, descending from the eye downwards, has a similar 



