- PTENODERA DUBIUS. 91 



a sub-order, Archiblattides, to receive many of the insects classed as Protorthoptera 

 by Handlirsch. 



The wing is apparently related also to Scalasoptera recta, Bolton, and as the 

 latter shows no trace of the formation of an anal lobe, I class this genus with the 

 Protorthoptera rather than with the Protoblattoidea. The Protoblattoidea 

 probably arose from a Protorthopteroid stock. 



Ptenodera dubius, sp. nov. Plate VI, fig. 2 ; Text-figure 28. 



Type. Distal half of a left wing, on the split surface of one half of an ironstone 

 nodule; British Museum (Johnson Collection, no. I. 1559). 



Horizon and Locality. --Middle Coal Measures (binds between the "Brooch" 

 and " Thick " coals) ; Coseley, near Dudley, Staffs. 



FIG. 28. Ptenodera dubius, gen. et sp. nov.; diagram of apical portion of wing, twice natural size. 

 Middle Coal Measures ; Coseley, Staffordshire. Johnson Collection, Brit. Mus. (no. I. 1559). 



Description. The ironstone nodule has been broken across, and that portion 

 which contained the basal half of the wing has been lost. The distal portion of 

 wing remaining is 27 mm. long, with a width of 16 mm. across the widest part. 

 The width of the basal half of the wing was probably greater. 



The distal half of the wing is thin and membranous, and a little wrinkled. 

 The principal veins are well shown, but the interstitial nervures are only clearly 

 visible when the nodule is immersed in water. 



The costa is marginal and gradually curves into a well-rounded wing-apex. 

 The subcosta is widely spaced from the costal margin basally, and gradually 

 approaches it as it passes out towards the wing-apex, which it does not reach. It 

 gives off to the wing-margin a series of oblique divisions, several of which fork. 



The radius is simple, and passes straight to the wing-apex. Somewhat widely 

 separated from the radius is the radial sector, which must therefore have been 

 given off low down in the base of the wing. It divides into two equal branches, 

 each of which is again equally divided, so that it ends on the middle of the wing- 

 apex in four divisions. 



The median vein is large and well branched. The nodule has been broken 



