580 MESOZOIC INSKCTS OF QUEENSLAND, iv., 



immediately divides into two; of these, the upper, Mg, runs to 

 tlie termen on a similar course to that of Mj, but well below it; 

 while the lower branch, M3, diverges from M2 for some distance, 

 until it gives off a backwardly descending vein, whose destina- 

 tion cannot l)e followed out in Dunstania\ at this point, M3 is 

 bent at a very oblique angle, and passes on probably to near the 

 tornus of the wing. 



From the base of M3, in Vutisfania, a very weakly indicated 

 vein, M4, can be made out, passing downwards, about midway 

 between Mg and the dividing line; it can be seen to be con- 

 verging towards the cross-vein mentioned in the preceding para- 

 graph; but the fracture of the rock hides its further course from 

 our view. 



In order to follow out the further structure of the w'ing, pos- 

 teriad to the region of M, we must now turn again to Duiistati- 

 iopsis (Text-fig. 18), in which mast of this part of tlie wing is 

 fairly well preserved. In this genus, we can easily pick up the 

 cubitus, running with a gentle curve upon the corium, well below 

 M. In Syroinastes^ we see that M and Cu are connected by a 

 short cross-vein, not far from the dividing line. In Dunstan- 

 iopsis^ Cu gives off an oblique anterior branch, which approaches 

 closely to two oblique posterior branches given off' by M at about 

 the same level; these two branches of M unite close to the 

 dividing line, at a point where the branch from Cu lies very close 

 below them. Here there is a break in the rock-surface; but we 

 can pick up, on the other side of the break, a single weak vein 

 curving into M4. This is evidently the prolongation of the 

 united branches from M and Cu. 



Turning now to the main stem of Cu, we can follow it, in 

 Dunstaniopsis^ up to the dividing line between corium and 

 membrane, where it gives off an oblique anterior branch, Cuj^; 

 this branch meets M4, the weak vein already mentioned as de- 

 scending from the base of Mo. At the angle formed by these 

 two, which is almost a right angle in Dunstaniopsis, a third vein 

 comes in from the membrane; following this distad, we see that 

 it arises from M3, which, in this genus, is a straight vein running 

 to near the toruus of the wing. 



