90 FOSSIL INSECTS OF THE BRITISH COAL MEASURES. 



part, of their length. Their costal area is also broader than the subcostal-radial 

 area, and in both families the interstitial nenration consists of straight cross- 

 nervnres, except in the costal area, where they are oblique, as in this specimen. 



These resemblances, however, are not sufficient to justify the inclusion of the 

 new wing among the Geraridre, because they are accompanied by equally or more 

 important differences, such as the spinulose character of the principal veins, the 

 great development of the intercostal area, the marked divergence of the stems 

 of the radius and the median, the coriaceous wing-membrane and the much fewer 

 cross-nervures. The wing, too, possesses quite a leathery texture, while the 

 cross-nervnres are broad and flat, forming conspicuous details of the surface. 



With our present knowledge, it is only possible to infer that the wing is 

 related to the Geraridre and Spanioderid;e, that it is a Protorthopteroid, and that 

 it still retains traces of its Palseodictyopteroid ancestry. 



Order PROTOBLATTOIDEA, Handlirsch. 



The Protoblattoids have a well-rounded head, a prothorax showing little or no 

 expansion, and the wings intermediate in type between those of Palasodictyopteroids 

 and Blattoids. The anal areas of the fore-wings or tegmina 1 are well marked out, 

 and crossed by arcuate or oblique veins reaching the inner margin, while those of 

 the hind-wings are enlarged and marked off from the rest of the wing by an anal 

 fold. The body is more slender than in the majority of Blattoids. 



The members of this order form a connecting link between the Palaeodictyoptera 

 and the Blattseformes. In manv respects there is a close resemblance between the 

 members of the order and those of the Protorthoptera, and the two may have 

 arisen from nearly related stocks. 



Genus PTENODERA, novum. 



Generic Characters. Subcosta reaching 1 almost to the wing-apex. Radial 

 sector twice furcate; median well divided, with its minor divisions crowded on the 

 inner half of the wing-apex. 



I have formed this genus to include a win^-fra^ment of unusual character in 

 which the principal veins are long, and directed towards the wing-apex with few 

 divisions, and the interstitial neurat inn consists of straight cross-nervures. The 

 specimen shows thai the brandling of the principal veins is much similar to that of 

 Polyetes among the Protoblattoidea, and to that of S/nniimli'i'ii scltuclierti, Hand!.. 

 ammiL!' the I'rnt nil hopt era. in this respect support iniy I'rnvost. \\lio has estab ished 



1 The thickened ri^i.l foiv-win^s of Bkitloi.ls uiv usually termed " li-iniiina." 



