15 



acted, at least partly, as a tegmen, and forming an intermediate 

 stage in the phylogeny of the present-day strong and narrow Orthop- 

 terous tegmen characteristic of many recent Locustoidea. 



The two wings agree in the following characters : The nature 

 of the costal area bounded by the straight subcosta below and 

 crossed obliquely by parallel cross-veins, the comparative sizes and 

 positions of Sc and R, the rather peculiar sculpture of the broad 

 radius (not shown in the figures but visible in the specimens with 

 careful lighting), the position and direction of the radial sector, and 

 the nature of the branches of the media. They differ only in texture, 

 width, density of venation, and probably in the form of the cubital 

 and anal veins. It will be seen that the fragment of hindwing is a 

 portion slightly nearer the base than that of the forewing, and shows 

 us not only a series of anal veins, but also the very characteristic 

 origins of the three anterior branches from the main stem of the 

 media. The a re hi rigs upwards towards the radius in the case of the 

 first two of these are very similar in both wings. In the forewing 

 there is preserved a wider area of the costal space, showing the 

 parallel oblique cross-veins to be unbranched distally. The close 

 double ro\v of cells between Sc and R in the forewing is in sharp 

 contrast with the apparently free corresponding space in the hind- 

 wing. The few cross-veins which can be made out in the hindwing, 

 e.g. those between R and the uppermost branch of M, show that the 

 venation of this wing was much more open than that of the forewing. 

 In the latter there is a dense system of small cells between all the 

 main veins. 



Turning to the specimen oc (Plate 1, fig. 4), this is determined 

 as part of a hindwing on account of its open venation. The slant of 

 the cross- veins forming the two upper rows of the specimen suggests 

 that the fragment lies close to the costal border. Apart from this, 

 if the specimen had been found alone there is nothing to suggest to 

 what order it might belong, the lower cross- veins suggesting a portion 

 of a large Odonate wing. 



MEASUREMENTS : Basal fragment of forewing (5a) greatest 

 length 12 mm., greatest breadth 8 mm. Basal fragment of hind- 

 wing (56) greatest length 11 mm., greatest breadth 8.5 mm. 

 Distal fragment of hindwing (5c) greatest length 9 mm., greatest 

 breadth 9 mm. 



TYPES : The three fragments, Specs. oa, 5b, oc (Plate 1, rig. 

 4 ; Plate 2, figs. 3-6). (B. D. Coll.) 



OBS. : The chief interest in this species appears to lie- in the 

 fact that it gives us a definite connection between Handlirsch's 

 Protorthoptera of the Carboniferous and Permian in the Northern 



