54 Dr. n. Woodward — British Carboniferous Cochroaclies. 



lost on the border of the nodule). The metathorax and abdomen 

 are not visible, being covered by the closely-folded wings. 



It has been a matter of no small difficulty to the artist accurately 

 to trace out the venation of the wings in this specimen. When a 

 single wing is preserved on the surface of a piece of shale, its veins 

 can usually be traced distinctly ; but when two pairs of superposed 

 wings have to be studied, they present, after compression, a some- 

 what complex problem to unravel. I believe, however, that the outline 

 (PI. II. Fig. Ih, and la, nat. size) gives a fairly accurate representation 

 of the veins. The wing is oblong-ovate in form ; the ' mediastinal ' 

 vein commences at the proximal end of the wing, about 3 mm. within 

 the border, and runs almost parallel with the superior marginal vein, 

 but gradually bends towards, and unites with it, at 20 mm. from 

 its commencement. It gives off, at first, several single branches, 

 followed by five equidistant bifurcating ones; the 'scapular' vein 

 takes its origin at the proximal end, close to the 'mediastinal' vein, 

 and after pursuing a course nearly parallel to it, it terminates on the 

 anterior distal margin of the wing, 25 mm. from its commencement, 

 giving off" five simple branch- veins from its superior border. The 

 ' externo-median ' vein takes its rise from the inferior side of the 

 ' scapular ' vein, about half-way in its course, and extending to the 

 extremity of the wing, it gives off one single superior and one bifur- 

 cated inferior branch. 



The 'interno-median' follows the course of the conjoined 'externo- 

 median ' and ' scapular' veins, arching towards the inferior or interno- 

 median margin of the wing, giving origin in its course to six inferior 

 branch-veins about equidistant from each other, the first (proximally) 

 being bifid, the second simple, the third, fourth and fifth bifurcated, 

 and the sixth simple. The anal area of the wing is strongly marked 

 by the arched anal vein which is branched, and is followed by about 

 five simple similarly arched veinlets, whose origin appears to be 

 along the inner proximal border of the wing. 



The whole surface of the wings exhibits a very delicate tracery 

 produced by the slighly-elevated microscopic net-work of cross-veins, 

 which need the aid of a magnifying glass to reveal, and are not 

 attempted to be represented in our Plate. ^ 



Several of the species of Etohlattina, figured by Scudder, present 

 a general resemblance in form and in the distribution of the veins to 

 our specimen ; but they differ materially in the area which the 

 branches of each principal vein occupies. There is not one in which 

 the ' scapular ' and ' externo-median ' veins rise half-way down the 

 wing from a common main trunk. This is a character which has 

 been frequently observed in the veins of the front wings, or tegmina^ 

 of existing species (Scudder). It would require, however, a far 

 larger series of specimens than we possess, and at least several 

 examples of each species (a consummation devoutly to be wished 

 for, but not the least likely to be fulfilled), before one could venture 

 to speak with any degree of confidence of species founded on such 

 fragmentary evidence as we at present possess. 



1 Mr. Scudder' s artist has siiccessfuUyreproduced this Avonderf ul and complex lace- 

 structure in Eloblattina venusta, Lesquereux (Scudder, op. cit. pi. 6, fig. 12, p. 70). 



