INSECTS OF NEW BRUNSWICK. 13 



The ■wing is that of a very large insect, the fragment, which reaches neither base nor 

 tip, being 60 mm. long, and rendering it probable that the alar expanse was at least 150 

 mm. and more probably 175 mm. The apex of the wing was pointed, the costal and outer 

 margin probably meeting at a rounded angle of about 60°. The costal margin must have 

 been very strongly arched near the middle of the apical half, \^llile the apical part of the 

 outer border is nearly straight. The wing was probably elongated, not very broadly 

 expanded in proportion to its length, as I at first presumed from not having counted on 

 such an extended development toward the base. In the middle of the outer half of the 

 wing the width is about 23 mm., and from the course of the fragments of the two borders 

 it is probable that the width nowhere exceeded 25 mm. or about two-sevenths the length of 

 the wing. The fragment preserved contains considerably less than half the area of the wing 

 comprising most of the central portions. The whole anal area is lost as well as what is 

 apparently most or all of the internomedian area, extending far along the outer margin ; 

 the merest fragment of the costal border, 2-3 mm. long, is preserved, apparently about 

 the middle of the wing ; the tip of the wing and outer half of the costal margin are 

 broken away, but a couple of veins at the tip are supplied, as already stated, from a piece 

 that was accidentally removed. This irregular fragment, extending diagonally across the 

 outer half of the wing, with a basal extension along the middle line, is traversed by 

 principal nervures bound together by a net work of mostly very irregular and very feeble, 

 occasionally more regular and distinct cross veins, forming irregular, mostly longitudinal, 

 unequal, polygonal, rarely quadrangular cells. The veins may be grouped into an upper 

 set of parallel, equidistant and rather approximate, nearly straight, slightly upcurved 

 nervures, three or four in number, traceable only near the middle of the wing ; and a lower 

 set of two, traceable throughout the apical half of the wing and extending nearly half way 

 from the middle to the base ; these are parallel, more distant, directed gently downward and 

 so divergent from the other set, and toward the apex curved considerably downward 

 Between the veins of the upper set the cross veins are infrequent and mostly straight, 

 forming quadrangular cells ; while in the lower set they are more frequent and very 

 irregular, forming polygonal cells which, toward the apical margin, are very indistinct 

 from the feebleness of the cross veins. 



The area formed at the apex of the wings by the divergence of the two sets of veins, 

 is filled by branches from the superior surface of the uppermost of the lower set of veins, 

 supporting a mesh of cross-veins. 



The principal vein of the wing then — the only one which appears unquestionably to 

 support a number of branches — is the uppermost vein of the lower set. And since in 

 all palaeozoic insects having true net-veined wings, one never has to pass beyond the 

 externomedian vein, in starting from the costal margin, to find the first extensively 

 branched vein, there can be little if any doubt that this should be considered as belong- 

 ing to that vein, and not to a lower one. The only difficulty about this interpretation is 

 that in the middle of the wing, there are above this vein no less than five equidistant and 

 almost equally distinct veins. The first of these, forming the margin, is the marginal 

 vein, and the next is the mediastinal. It is impossible to consider this marginal as the 

 mere thickening of the border, and the vein next removed from the border as the true 

 marginal vein, for both the margin itself would be too broad, and tHe marginal would 



