BY R. J. TILLYARD. 



that, in the forewing, the branchings of M spread out more 

 widely from their common stalk than they do in the hindwing. 

 Now, if we compare these conditions with the two fossil wings 

 of Permochorista, we shall see at once that P. australica resembles 

 the hindwing of T. pallida, both in its narrowing towards the 



M: 



'2b 



Text-tig.6. 

 Restoration of the typical venation for the genus Permochorista, n.g. 

 Forewing restored from P. mitchelli, hindwing from P, australica; fr, 

 frenulum; //, jugal lobe; pf, pterostigmatie furrow^; pt, pterostigma, 



base, and in the direction taken by the branches of M from their 

 common stalk; the principal difference being that, in 7'. pallida, 

 M sends only four branches to the wing-border (as in all recent 

 Mecoptera, except Merope, which has five), whereas in P. aus- 

 tralica there are no less than six. The position and number of 

 the branches of Rs is the same in both P. australica and T. 

 pallida. The only other important difference is to be found 

 in the slight irregularity of the courses of the main veins in T. 

 pallida, as contrasted with the absolutely regular main veins of 



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