••llili 



Ilitntll irsch —New Paleozoic Insects. 



case, but as they are also present in the wings of the related 

 form S/i//o//o/.s/i(,i\ I think they will prove to be organic struc- 

 tures of these insects. Dr. Reis has found similar but smaller 

 structures on the wings of one of the Protodonata of Triassic 

 age. Tubercles on the membrane have also been found in one 

 of the Palseodietyoptera. 



Holotype in Peabody Museum, Yale University, Cat. No. 41. 



Spilomastax, new genus. 



Spilomastax oligoneurus, new species. Fig. 3 1 . 



Two fragments evidently appertaining to the left and right 

 anterior wing of a comparatively small insect, whose wings can 

 be estimated at 30-35 min . Subcosta far removed from the 

 marginal costa and provided with regular oblique branches. 

 Radius giving off its sector at about the middle. Media send- 

 ing the typical short and oblique branch to the cubitus at about 

 a quarter of its length and split into a large fork befoi'e attain- 

 ing the middle of the wing. Cubitus cleft immediately after its 



Fig. 31. 



Fig. 31. Spilomastax oligoneurus. x 2. 



origin, the anterior branch waved, sending 4 branches obliquely 

 outward and backward, the first 2 of them not reaching the 

 margin ; but the posterior main branch running straight and 

 undivided to the end. First anal vein gently curved, second 

 swung forward toward the first. Cross veins irregular, here 

 and there ramified but not twisted into a polygonal network. 



Both wings show numerous quite irregularly distributed 

 shallow round bodies similar to those in Cacurgus. 



Holotype in Peabody Museum, Yale University, Cat. No. 42. 



[To be continued.] 



