BRODIA PRISCOTINCTA. 65 



beyond the middle of the wing. It is close to the margin and parallel with it for 

 its whole length. The radius is well marked, sunken, and also parallel with the 

 margin except distally, where it is more inwardly curved. It ends on the apex in 

 a short fork. The radial sector arises near the base, and is parallel with the radius. 

 It appears to give off three to four branches, the first arising very near the base of 

 the wing. The whole course of this branch can be traced, but of the middle two 

 only faint traces are left in the region of the wing-apex. The fourth branch is 

 very short, and corresponds in position with the last branch of the radial sector in 

 Brodia priscotincta. The median vein forks low down into two equal branches, 

 which reach the middle of the inner margin. 



The cubitus is a long undivided vein passing out almost to the middle of the 

 inner margin, and separated from the next vein, which seems to be the first anal. 

 The course of the latter is more oblique to the inner margin than that of the 

 cubitus. 



In its general character this wing is distinctly similar to that of B. priscotincta, 

 although it lacks a second branch to the median, and the first anal does not seem 

 to be forked. 



Fig. 18. — Brodia priscotincta, Scudder, forma juvenis, Bolton j diagram of wing--neuration, twice natural 

 size.— Middle Coal Measures (binds] between the "Brooch" and "Thick" coals); Coseley, 

 Staffordshire. Madeley Collection, Brit, Mus. (no. I. 1564). Lettering as in Text-fig. 16, p. 62. 



Affinities. — Handlirsch regards these as nymphal wing-sheaths, but their 

 extreme tenuity militates against this view. He is probably wrong in referring 

 Brodia to the Megasecopterida?, but right in regarding these wings as those of 

 heterometabolous insects, and not holometabolous as Lameere supposed. 



Immature though the wings undoubtedly are, the more nearly perfect example 

 possesses an assemblage of characters which I believe points to its relationship. 

 The shape of the wing, the character and course of the subcosta, the number and 

 position of the branches of the radius, the simple forking of the median and the 

 anal veins, are all characters pertaining to the genus Brodia. The differences in 

 detail between this wing and that of B. priscotincta are such as may be looked for 

 between the nymph-stage and the adult. Among previously described larval wings, 

 the only type which seems comparable is Lameerpites curvipennis, Handlirsch, based 

 on four nymph-wings or wing-cases, as Handlirsch has them, found in the Coal 

 Measures (Pennsylvanian) at Mazon Creek, Illinois, U.S.A. (1911, Handlirsch, 

 ' Amer. Journ. Sci.' [4], vol. xxxi, p. 375). 



In these wings, the outer or costal margin is more strongly curved, and .the costa 

 and radius extend over the bluntly curved apex down to its junction with the 

 inner margin. The succeeding veins arise nearer the base of the radius, only one 

 9 



