462 SAMUEL H. SCUDDER ON 



the veins delicately impressed, the anal furrow apparently no more deeply than the 

 others. The wing is very regularly elongate elliptical in form and about two and three- 

 fourths times longer than broad. The extreme base is broken, but the flat humeral 

 held is apically pointed and tapering, and apparently just about as long as the width of 

 the wing. The characters of the costal nervules are just about intermediate between 

 those of M. Brodiei and M. Mantetti, the area being broadest in the middle, where it is 

 very nearly half the width of the wing and extends to the exact tip of the wing. The 

 externomedian and internomedian veins are also about intermediate between the same 

 two species, though their terminal area is almost exactly as in M. Brodiei. It differs, 

 however, from both of these species in the very regular form of the wing. The anal 

 furrow is precisely as in M. Hopei and terminates on the margin just short of the tip of 

 the humeral field. 



Length of fragment, 10.5 mm.; probable length of wing, 11.6 mm.; breadth of same 

 4.1 mm. It is named for Mr. B. X. Peach of the Geological Survey of Scotland, and 

 comes from the English Purbecks. 



Mesoblattina angustata. 



Blattina angustata Ileer, Viertelj. naturf. Gesellsch. Zurich, ix, 288, 299-300, PL, fig. 6. 

 Blattina {Mesoblattina) angustata E. Gem., Zeitschr. Deutsch. geol. Gesellsch., 1880, 



519-520. 

 Mesoblattina angustata Scudd., Proc. Acad. Nat. Sc. Philad., 1885, 111. 



This species, which is well figured and described by Heer, is conspicuous among the 

 species of Mesoblattina for its wedge-shaped form, in which it closely resembles a 

 Bithma. The course of the internomedian branches contends, however, against this, and 

 besides, all the anal veins cluster apically toward the tip of the anal furrow, as often in 

 Mesoblattina, and never, so far as known, in Rithma. The costal area occupies half the 

 wing and the humeral field, of which Heer makes no mention, must be very small, 

 slender and short. 



Length of wing - , 8 mm.; breadth, 2.5 mm. It comes from the Lias of Schambelen, 

 Switzerland. 



Mesoblattina Mathildae. 



Blattina Mathildae E. Gein., Flotzform. Mecklenb., 29-30, PL 6, fig. 1. 



This somewhat aberrant form of Mesoblattina has been wrongly interpreted by Dr. E. 

 Geinitz, as he has mistaken the inner for the costal margin and vice versa. The base 

 of the wing is broken, but the fragment seems to represent an elliptical wing, a little 

 more than two and one-half times longer than broad, with the lower outer edge rounded 

 off, so as to bring the tip of the wing above the middle line. No trace of a humeral 

 area can be seen, and it must be confined to the broken base and therefore short. The 

 mediastino-scapular vein (anal and part of internomedian of Geinitz) is pretty strongly 

 and regularly arcuate in the fragment (probably with a reverse curve, so as to be sin- 

 nous, toward the base), terminating just above the elevated tip of the wing, broadest 

 in the middle, where it is more than two-fifths of the breadth of the wing, all its branches 

 a little longitudinally oblique and parallel, the basal ones simple, the outer forked or 



