92 FOSSIL INSECTS OF THE BRITISH COAL MEASURES. 



across just beyond the point of division of the two main branches. The outer 

 branch remains undivided until near the margin, where it forks twice, ending on 

 the inner side of the wing-apex in three divisions. The inner branch forks into 

 two equal twigs, the outer breaking up twice by equal forking into four divisions, 

 while the inner twig forks once. Most of the divisions of the inner branch of the 

 median end on the distal portion of the inner wing-margin. 



Two incomplete branches of the cubitus are present, but the character of the 

 vein cannot be determined. No traces of the anal veins are shown. 



The principal veins and their main branches are well spaced, and follow the 

 same general direction without being truly parallel. The interstitial neuration 

 consists of fine straight cross-nervures. 



Affinities. The general character of the veins other than the subcosta is seen 

 in several Palaeodictyopteroid genera such as Eubleptus, but in none that I know 

 are these characters accompanied by a similar type of subcosta. In the oblique, 

 forked divisions of the latter, and the manner in which they are given off, as well 

 as in the course of the subcosta itself, the wing most resembles that of the Proto- 

 blattoids, and to this group I would assign it. 



INCERT^ SEDIS. 



Genus PLESIOIDISCHIA, Haridlirsch. 

 1906. Plesioidischia, Handlirsch, Die Fossilen lusekteu, p. 346. 



Plesioidischia sp. Plate VI, fig. 3 ; Text-figure 29. 



Type. A fragment of a right wing, 40 mm. long and 10 mm. wide ; 

 Manchester Museum (no. L. 4905). 



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

 " Thick " coals) ; Tipton, Staffs. 



FIG. 29.-Plesioidischia sp ; diagram of venation of wincf-fragment, three-halves natural size.-Middle 

 Coal Measures ; lipton, Staffordshire. Manchester Museum (no. L. 4905). 



Description. The wing-fragment lies on the irregular surface of a small 

 ironstone nodule, the outer costal margin and costal area on one half of 

 the nodule, and the middle portion of the wing on the other. The base 



