HEXAPOD INSECTS OF GREAT BRITAIN. 215 



played by the externomedian vein, which is frequently almost entirely simple or only 

 forked once in the apical half of its course. This peculiarity is borrowed, though not in 

 a striking degree, by Brodia, where this vein is forked once near the middle ; but whose 

 branches, widely distant like those of the scapular vein, cover a considerable area. 



The more essential features of this ancient wing, however, foreshadow the characteristics 

 of the Sialina. In form, while it is not very different, it has none of the arching of the 

 costa almost universal among Sialina, and usually accompanied in modern types by a 

 broad space between the marginal and mediastinal veins, not at all displayed by Brodia. 

 In the brevity of the mediastinal vein Brodia resembles the Raphidiidae, but the neura- 

 tion of the rest of the wing is completely different ; while in the Sialina proper the medi- 

 astinal vein always continues nearly to the tip of the wing. The course and distribution 

 of the branches of the scapular vein, however, are of greater importance, and in this 

 respect Brodia agrees very well with the Sialina ; again, however, the simnlicity of the 

 internomedian vein in Brodia, where it consists of only a single undivided ray, is very 

 different from that now found in Sialina, where it is always divided and often plays a some- 

 what important part. 



Brodia, then, is a planipennian in a broad sense, refusing to affiliate closely with the 

 restricted families of the present day. Nor does it appear to be intimately related to any 

 paleozoic insect yet described. It is also peculiar for possessing a very large number of 

 fine cross-veins or wrinkles, besides the stout cross-veins which are scattered here and 

 there over the wing ; the latter are, however, confined to dark patches to be mentioned 

 presently ; while the former are uniformly distributed over the wing, subequidistant, and 

 always run at right angles to the nervures they connect, even where, by keeping that 

 course, they strike the often obliquely directed, stouter cross-veins. 



In the preservation of its colors (pi. 17, fig. 7), Brodia is the most striking instance 

 known among paleozoic insects the markings are sharply defined and, to judge from illustra- 

 tions, more deeply tinted than in Protophasma Dumasii recently described by Brongniart, 

 who has drawn particular attention to this remarkable feature in the wings ; or than in the 

 longer known Gryllacris lithanthraca of Goldenberg. In allusion to this colorational fea- 

 ture, the species may bear the name of 



Brodia priscotincta nov. sp. 

 PI. 17, figs. 3-7. 



The wing is a rather large one, being probably about 55 mm. long (the fragment is 44 

 mm. long) and 12 mm. broad in the middle. Both front and hind margins are very dark 

 colored and are distinctly furnished at the extreme edge with a row of fine bristly teeth, 

 short, stout, triangular, pointed, black, directed outward and forward (or backward), and 

 on the costal edge more closely approximated away from (pi. 17, fig. 5) than near (pi. 17, fig. 

 6) the base ; beyond the base, also, the marginal vein is furnished along its lower edge with 

 a similar armature, only the teeth, here also black, are depressed, directed outward, and 

 not nearly so sharply pointed (pi. 17, fig. 5). 



The stone on which the wing is preserved is of a dull, impure gray color (pi. 17, fig. 7), 

 and the hyaline parts of the wing do not differ from it in tint. Nearly half of the wing 



