TILLYARDIA MULTIPLICATA. 145 



divided. Accessory sectors present. Interstitial neuration forming a regular 

 series of straight cross-nervures. 



I refer to this genus a highly specialised wing from the Scottish Coal Measures, 

 which is unlike any other Carboniferous wing that I know. It is at once suggestive 

 of the Palasodictyoptera and of the Protodonata, but belongs, I believe, to the 

 latter Order. Where shown, the neuration of the wing is clear, and the absence 

 of the outer part of the base, and the central portion of the wing, renders it 

 difficult to determine the actual course of certain veins and their true nature. 



I have much pleasure in naming this genus after Dr. R. J. Tillyard, whose 

 researches on the venation of the wings of nymphs of recent insects have helped 

 to interpret the older fossil forms. 



Tillyardia multiplicata, sp. nov. Plate X, fig. 2; Text-figure 45. 



Ti/p<'. Greater part of the impression of the under surface of a right wing; 

 Museum of Geological Survey of Scotland, Edinburgh (no. T. 4098?'). 



Fio. 45. Tillyardia multiiilicatu, sp. nov.; diagram of venation of right wing, enlarged 

 one-and-a-half times. Upper Coal Measures; Barony Pit, Auchinleck, Ayrshire. Museum of 

 Geological Survey of Scotland, Edinburgh (no. T. 4O98 b). 



Horizon and Locality. Upper Coal Measures; Barony Pit, Auchinleck, Ayrshire. 



Specific Characters. As above. 



Description. The wing lies on the irregular surface of a soft purple sandstone, 

 is imperfect, and has been badly rubbed, so that the junctions of some of the veins 

 have been obscured. The whole of the base of the wing is missing, and the 

 middle portion of the impression of the wing has also been destroyed. It is 

 67 mm. long and 13 mm. wide. 



The outer margin appears to have been almost straight over the greater part 

 of its length, inclining gently into the wing-apex, the latter joining the inner 

 margin in a blunt right-angle. By analogy with the Protodonata, the outer 

 margin was extended outwardly in its basal half, and the subcostal area was 

 widened out. This feature is seen in Paralogus seschnoides, Scd., with which the 

 wing has much in common. No trace of an undoubted subcostal vein is dis- 

 tinguishable. It must therefore have been short, and joined to the outer margin 

 in the basal half. The radius is a long vein, parallel with the outer margin, and 

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