(BLATTOIDEA) PEAOHI. 135 



Horizon and Locality. Coal Measures ("grey sandy shale with nodules of 

 impure clay and ironstone" at 91 ft. 6 in. below the surface); Greenhill Pit, 

 Kilmarnock. 



Description. The length of the insect is 23 mm. and its width across the fore- 

 wings 15 mm. The pronotum is 12 mm. wide, and 5 mm. long. The abdomen is 

 12 mm. long and diminishes in width from before backwards. The coarse 

 character of the stone has obliterated or failed to preserve all the finer detail of 

 the specimen, but the insect still retains the gently convex dorsal surface which it 

 doubtless had during life. 



The very small head, not well defined, is apparently divided into two small 

 anterior and two larger posterior areas by shallow longitudinal and transverse 

 grooves. No appendages are visible. A raised V-shaped portion of the matrix in 

 front of the head may indicate that it formerly extended beyond the line of the 

 pronotum. The two anterior plates covering the head are notched in a small v on 

 the middle outer edge. 



The pronotum is nearly two-and-a-half times as wide as long, with rounded 

 latero-posterior angles and almost straight posterior border. The front border 

 forms a semicircle, recessed in the middle, and enclosing the head-shield termed by 

 Dr. Henry Woodward an " epicranial plate." 



Two pairs of rudimentary wings are present, the first pair articulating well 

 forward, as if attached to the mesonotum under the hinder margin of the pronotum ; 

 the hinder pair being joined to the metanotum nearer the middle line. The wings 

 are about 10 mm. long and 5 mm. wide, with blunt apical angles. The front pair 

 of wings have begun to take on the character of tegmina, being stouter than the 

 inner pair. 



The venation of the wings is but faintly indicated. Woodward has stated 

 that the " mediastinal " vein and the veins of the anal and intermedian area are 

 seen in all four wings. In present nomenclature this means that the subcosta 

 and the cubitus are present, with some traces of the anal veins. 



This seems hardly to be the case. The left hind-wing has the veins best 

 marked, and all that can be said is, that there are indications of a few short, thick 

 veins passing from near the attachment of the wing towards the inner margin, and 

 crossing the middle of the wing. The condition is much like that figured by 

 Comstock and Needham (< Amer. Nat/ [4], vol. xxxii, p. 773, fig. 56, 1898) in the 

 hind-wing of the nymph of a cockroach, except that the veins in the Kilmarnock 

 specimen spread fanwise, instead of keeping in close order down to the wing-apex. 

 The veins present will therefore agree best with the radius, median and cubitus. 

 The vein which I consider the radius is nearly parallel with the outer margin and 

 better defined than the rest. 



The length of the mesonotum and metanotum together is 6 mm. Neither is 

 well seen owing to the overlap of the wing-bases. 



