28 FOSSIL INSECTS OF THE BRITISH COAL MEASURES. 



Ifnri-nn mid Locality. Middle Coal Measures (below the Top Hard Coal I ; 

 Shipley Manor Claypit, llkeston, Derbyshire. 



Specific Characters. Radial sector reaching the inner half of the wing-tip. 

 Outer branch of median four or five times divided, inner branch simpler and 

 forked. Cubitns dividing low down, the outer branch the stronger, and each 

 doubly forked. Anal veins one or two in number, alternately branched. 



Ih'xi-ri/itinii. The species is founded on a wing-fragment, the apex, a portion 

 of the inner margin, and the base being incomplete. The total length is 84 mm.. 

 the width oo mm. The complete wing must have had a length of at least 10(.) mm., 

 and a width of oo 40 mm. The whole insect had in all probability a span of 

 wing measuring 'J-Vo cm. ( 1 in. or more). 



The outer third of the wing is differentiated from the rest by its uniform and 

 gentle convexity, and by the character of the costa, snbcosta, radius, and median 

 veins, which pass outwards towards the wing-apex in straight lines, and show no 

 trace of divisions until well beyond the middle of the wing, contrasting strongly 



VIG. l.~ Orthocosta S/'/OM^OIS. liolu.n ; ivsturatiuii .i| winy, showing portiuii invsi-rvril and tin- 

 rliara.-!iT i>f tliu intrrstitial iii-uration. natural si/,c MHilli- C.ial Pleasures (In-low the '\'"\* 

 Hani Cciiil) ; Shipley Manor ( 'laypit , Ilkr.stoii. 1 Irrl.yslmv. Moysi-y t 'olhvtion, Mus. Pi-art . < ici.l. 

 (noa :io.L'i'L' an.l :id,L'j:i). 



with the areas occupied by the marginal divisions of the median, cubital and anal 

 veins. The inner two-thirds of the wing is marked by deep furrows, in which lie 

 the marginal branches of the median vein, and the whole of the cubital and anal 

 veins. The areas between any two veins in this region are markedly convex. 

 The differences in character of the outer and inner portions of the wing are empha- 

 sised by a line of fracture which fairly accurately separates the two. Its occur- 

 rence Miggest> that it has followed a nat ural line of weakness, the more delicate 

 inner part of the wing breaking a\\a\ from the outer stronger portion. 



The costa, subcosta, radius and median are all well-developed veins, stout in 

 structure and standing out in relief. The first three retain this evidence of 

 -treiigth over two-thirds of their length, the median vein showing signs of 

 attenuation beyond the proximal third. 



The general structure of the wing indicates considerable powers of Might. 

 The outer margin, of which only a portion is preserved, appears as a stout, slight l\ 

 elevated and well-rounded ridge. 



The subcosta agrees in general character with the costal remnant, and is 



