118 S. H. SCUDDER ON PALAEOZOIC COCKROACHES. 



Goklenberg compares the species to Etobl. euglyptica, from which he says it differs in its 

 larger size, broader mediastinal area, larger number of branches in the anal area, and a 

 wider interspace between the scapular and internomedian areas. The differences between 

 the two species in every part of the wing are so great that it is difficult to see any special 

 point they have in common, excepting the simplicity of the internomedian and anal 

 branches, which is common to a great number of forms. Goklenberg subsequently com- 

 pares this species to Etobl. anaglyptica, with which it agrees better both in shape and 

 in neuration, but it is still larger than that species, and differs besides in the brevity and 

 non-production of the internomedian area. It much more closely resembles Etobl. pri- 

 maeva than either, although still widely distinct from it. From the only other species of the 

 genus it is distinguishable by the brevity and unequal breadth of the mediastinal area, 

 the inferior origin of the externomedian branches, and the tapering form of the wing. 



Several specimens must have been found in the iron-stone nodules of Lebach above 

 Saarlouis, Germany, as Goklenberg remarks that it appears there to be common. Dyas. 



We come now to the more aberrant forms of this group of carboniferous cockroaches, the 

 preceding genera being more closely allied to each other than to either of the groups 

 which are to follow, and which comprise between them but five species. 



Progonoblattina nov. gen. (jzpdyuvtx;, Blattina). 

 Blattina Auct. (pars). 



In the genus now under consideration the mediastinal vein of the front wing runs par- 

 allel and near to the costal border, occupying, even in the slender species, less than a third 

 of the breadth of the wing, and terminating only a little beyond the middle of the costal 

 margin ; its branches are frequent, oblique, gently arcuate, and simple. The scapular vein 

 is of much greater importance, commencing to branch far toward the base of the wing, 

 emitting five or six forking branches, and terminating only just before the tip of the wing; 

 the branches are superior, but longitudinal or scarcely oblique, and at the termination of 

 the mediastinal vein the are aoccupies about half the breadth of the wing. The exter- 

 nomedian vein early divides into several principal branches, which are very similar in 

 nature to those of the preceding vein, and occupy on the margin a similar extent ; ac- 

 cording, however, to the curve of the main scapular vein, this area may occupy, with its 

 many doubly forking longitudinal branches, more or less room than the scapular area; to- 

 gether tlie}^ occupy the entire apical half of the wing, and more than a third of the basal 

 half. The internomedian vein, which originates in the middle of the base of the wing, 

 slopes in a more or less arcuate curve toward the middle of the inner margin ; it emits 

 only three or four branches, simple or apically forked, and altogether plays a very insignifi- 

 cant part in the wing, the anal furrow, which is slight and considerably more arcuate than 

 the internomedian vein, terminating beyond the middle of the basal half of the wing. The 

 anal veins are more oblique than the anal furrow, not very numerous, subparallel, and 

 simple or forked. 



Nothing but upper wings are known, and these vary exceedingly in slenderness, one of 

 the two species being the slenderest known species, while the other is a little below the 

 general average. 



