466 MESOZOIC INSECTS OP QUEENSLAND, ix., 



Division CBYPTOCEBATA. 



Family TRIASSOCORIDAE, n.fam. 



Insects resembling the Naucoridae and Galgulidae in the form of the 

 hemelytron, which is broad, with a strongly projecting elavus reaching half-way 

 or less along the posterior margin, and strongly angulated. Tegmen smooth, 

 dark and shiny, as in Naucoridae, and not tough or marked with paler patches 

 as in Galgulidae; the main veins R, M and Cui are still visible on the corium, 

 which extends over the greater portion of the hemelytron and is separated from 

 the narrow distal membrane by a definitely impressed line, ■ more or less con- 

 centric with the wing-border. In the region of the membrane above the apex, 

 R and M give off a series of radiating branches which cross the membrane at 

 close and regular intervals; most of these are only faintly outlined. These 

 characters agree with those of the Belostomatidae of the present day, from which 

 the fossil family is distinguished by its much smaller size and different shape. 

 It would appear to be ancestral to the three families Galgmlidae, Naucoridae and 

 Belostomatidae, and perhaps to all the rest of the Cryptocerata also. 



Genus Triassocoeis, n.g. (Text-figs. 87, 88. ) 



Hemelytron short, broad, quite smooth in texture, shiny and also very 

 darkly coloured. Venation mostly very faintly marked, only three main veins 

 apparent on the corium, viz., R, M and Cm. R and M are fused basally for 

 some distance. R rans about parallel with the costal margin, a considerable 

 distance from it; about one-third from base, it gives off a faint oblique veinlet, 

 which is probably the first of the series of radiating veinlets continued around 

 the apex, but mostly too weakly formed to be made out with certainty. M and 

 Cui both very faint, becoming irregular distally, and breaking up into small 

 branchlets, most of which are too faint to be indicated accurately in the figure. 

 Below Cm there is an appearance of a very faint, irregular, polygonal mesh- 

 work; this is more clearly marked in specimen 1676 than it is in specimen 140. 

 The division between corium and membrane distally is indicated by a curved 

 line running round from the end of R concentrically with the rounded apical 

 margin. In the region of the apex, especially above it, a series of radiating 

 veinlets can be seen crossing the membrane; they are clearly branches of R and 

 M which cross the concentric line above mentioned. Clavus short and broad, 

 strongly angulated, and ending up about half-way along the posterior margin 

 of the wing, with which it makes a very marked angle. The position of J;he two 

 hemelytra on the back of the insect when at rest is shown in Text-fig. 88, the 

 shaded portions being the two clavi. 



Genotype, Triassocoris myersi, n.sp. (Upper Triassic, Ipswich). 



Teiassocoris myersi, n.sp. (Text-figs. 87, 88.) 



Total length, 5.8 mm.; gr£atest breadth, 2.5 mm. Hemelytron broad and 

 well rounded apically; the corium and membrane quite smooth, apparently shiny 

 in life, and probably of a very dark colour, since specimen 140 is very much 

 darker than the rock on which it lies, but is clearly not cai-bonised. The vena- 

 tion of the corium is very faint, but the courses of M and Cui upon it can just 

 be made out in a strong oblique light, as well as a small portion of the poly- 

 gonal meshwork, in specimen 140; in specimen 1676, this meshwork is more 

 clearly marked, and very irregular in form. 



