BY R. J. TILLYARD. 



577 



called the corfwm (co), and a softer membranous distal half, called 

 the meAnhrane (ni). These are separated by the dividing line, 

 running somewhat obliquely across the wing from the node (n) 

 on the costa to the antinode (n) on the dorsum. Posterior to 

 the corium is a narrow projecting anal area, known as the cl(wiis 

 (cl). Around the membrane is a complete coriaceous harder (e.b.), 

 such as we have already noticed very prominentlv in the tvpe- 

 specimen of Dnnst<iiiia. 



Text-fig. 18. 



Hemelytron of Dunstaniopsis triamica, n.g, et sp.; { x2*S). Upper 

 Triassie, Ipswich, Q. For lettering, see p. 592. 



Turning next to Dunstaniopsis (Text-fig. 1 8) we see that the 

 node is more prominent, but that the dividing line is, on the 

 whole, not so clearlv marked, and its course is far more irregular. 

 This line also runs more transversely across the wing in Dun- 

 staniopsis than in Syromastes-, but, in many recent Heteroptera, 

 especially in the family Pentatomidce, it takes a similar trans- 

 verse course, though much straighter than m Dutistaniopsis. A 

 further point of difference is that no true claval area can be seen 

 in Dunstaniopsis. But, as the extreme base of the wing is not 

 preserved, there may well have been a short elavus present on 

 the lost part. 



Turning next to the venation, we notice that, in Syromastes, 

 the corium is crossed by four longitudinal veins, not counting 

 the analis, which borders the elavus anteriorly. By reference 



44 



