170 PROCEEDINGS OP THE AMERICAN ACADEMY 



Tho group originally contained three species, which are here divided 

 among the three genera so far discussed. As restricted, the species 

 are the following : — 



1. Wings exceeding seven centimetres in length ; the scapular branch 

 originating at about the middle of the wing . D. Schmitzii Gold. 



Altenwald (Saarbrnck basin). 



1. Wings not exceeding five centimetres in length; scapular branch 



originating much before the middle of the wing 2 



2. Branches of scapular and externomedian veins very dissimilar ; those 



of the latter much more numerous . . D. Humholdtiana Gold. 



Sulzbach (Saarbruck basin). 



2. Branches of scapular and externomedian veins similar ... 3 



3. Main scapular branch first forking far beyond the middle of its 



course D. sinuosa Kliv. (Saarbruck basin.) 



3. Main scapular branch first forking before the middle of its course. 

 D. affinis (Tej-mes qffinis Gold.). Sulzbach (Saarbruck basin). 



PoLiOPTENUS (xoAto?, TTTT^vos), n. gen. 



A single species. Diet, elcgans Gold., from Dudweiler, in the Saar- 

 bruck basin, is separated from the others to which it is allied, on 

 account of its forked intcrnomedian, wdiich has here almost the impor- 

 tance of the externomedian. In other respects, it agrees in general 

 features with Dictyoneura. 



PuOTOrnASMA Brongniart. 



» 



It was in founding this genus that Brongniart made known the re- 

 lationship of the wings allied to Dictyoneura, heretofore considered 

 neuropterous. The wing of Protophasma, as figured by Brongniart, 

 however, differs plainly from any of the genera here distinguished, 

 althonch it seems certain that his delineation of the neuration cannot 

 be considered strictly accurate, as it is very anomalous, and probably 

 distorted by its preservation. We have not attempted, therefore, to 

 })lace it in our table, though the position of the genus is somewhere 

 among those in which the scapular nervure is simple. A single species 

 is known, Prot. Dumasi Brongn., Commentry, France. 



Breteria De Borre. 



Much discussion has arisen concerning the aiTniities of the single 

 wing upon which this genus was founded, which will be found princi- 



