470 SAMUEL II. SCUDDER ON 



The length of the fragment is !> nun., its breadth 5 mm. Probably the wing was 12 

 mm. long, and 5.5 mm. broad. It was [bund in the Corbula or Peeten beds of the 

 middle Purbecks of Dorset, England. 



Pterinoblattina penna. 



PI. 48, fig. 14. 



Pterinoblattina penna Sendd., Proc. Acad. Xat. Se. Philad., 1885, 10G. 



The single specimen of this species at hand is preserved in much the same manner as 

 the last, but shows a fragment of the anal region. The specimen is of the same color as 

 the dirty chalky-white stone on which it rests. The median area is scarcely concave, the 

 vein depressed ; the mediastinal area is slightly convex and its main stem is elevated ab< »ve 

 the two next below it. The three principal veins approach each other very gradually 

 so as to give them the appearance of a tapering rod. The mediastinal branches part 

 from the stem at nearly a right angle near the base of the wing, gradually increasing in 

 obliquity distally, until they form an angle of 45° with it; they are slightly curved, the 

 concavity outward, very closely crowded, and about every third one forked near the mid- 

 dle, bnt with no regularity. The scapular branches are not preserved, but as in P.jiluma, 

 and for the same reason, they probably resemble P. clirysea rather than P. intermixta. 

 The median branches are very closely crowded, generally straight, part from the stem at 

 an angle of 45° next the base, and become almost wholly longitudinal at the apex; they 

 fork about as frequently as, and more irregularly than, the mediastinal branches. The 

 anal area extends far out on the wing, and its branches (what few can be seen) resemble 

 those of the preceding area, and at its extremity are parallel to them. 



Length of fragment, 13 mm.; width, 9 mm. Probable length of wing, 15 mm.; prob- 

 able width, 9 mm. Described from a specimen from the English Purbecks sent me for 

 examination by Rev. P. B. Brodie. 



It is not impossible that the fragment of a larger wing figured without name by 

 Westwood (Quart. Journ. Geol. Soc. Lond., x, PL 17, fig. 7) , from the Lower Purbecks 

 of Durdlestone Bay may be a species very close to this, if indeed it is not the same. 



Pterinoblattina chrysea. 



Blattina chrysea Gein., Zeitschr. Deutsch. geol. Gesellsch., 1880, 520, PI. 22, fig. 2. 

 Pterinoblattina clirysea Scudd., Proc. Acad. Xat. Sc. Philad., 1885, 106-1<>7. 



In this case we have a more perfect wing, the tip being almost completely preserved. 

 The mediastinal vein terminates before the middle of the outer half of the costal border, 

 and is furnished with simple, straight, oblique branches, not so numerous as in the other 

 species, to judge by the figure, though they are spoken of by Geinitz as "very numerous 

 and closely crowded." dust before the scapular reaches the tip of the mediastinal, it 

 turns parallel to the costal margin, runs to the upper tip of the wing, and emits branches 

 similar to those of the mediastinal, but of course of equal length. All the median 

 branches run almost longitudinally, art' straight, sometimes forked, and appear from the 



