80 



PALEONTOLOGY 



{b) by the single anal vein (Fig. 41). In the latter feature they 

 approach the Megasecoptera, but the broad wing bases and the 

 close meshwork of cross- veins readily separate them. The 

 Meganeuridse include the largest of all fossil insects with a wing- 

 expanse in some species which exceeds 2 feet. The order may be 

 divided into two families. 



1. Fam. Protagriidce. Both the main branches of M and Cu 

 present. Protagrion Brongn, Upper Carboniferous of Commentry, 

 France. Calvertiella Till., Lower Permian of Kansas. 



2. Fam. Meganeuridce. Veins MP and CUj vestigial or absent 

 Meganeura Brongn., Upper Carboniferous of Commentry, France ; 

 Lower Permian of Germany and North America. Megatypus 

 Till., and Typiis Sell., Lower Permian of Kansas. Boltonites. 



Fig. 41. Wing of Protagrion audouini Brongn. Restoration of wing ; 

 cross-veins omitted (length about 00 mm.). (After Tillyard, 

 Rec. Ind. Mus., XXX., 1928.) 



Upper Carboniferous of Somerset, England. Paralogus Scud., 

 Upper Carboniferous of North America. 



Protoperlaria Till. (Mio^noptera, jmrtini Martynov). This order 

 differs from the Plecoptera (or Pcrlaria) in the presence of 5- 

 segmented tarsi, well-developed j)ronotal expansions to the 

 prothorax and of both main branches (MA and MP) to the media 

 (Fig. 40). Its limits are as yet imperfectly understood, and 

 probably certain types relegated to other groups belong here. 

 So far representatives have only been found in the Permian rocks 

 of Kansas and of North Russia. The Kansas examples were 

 originally placed by Sellards in new families of Protorthoptera 

 and subsequently Martynov (1927) erected the order Miomoptera 

 for their reception along with the family Palteomantidte Handl., 

 and new forms discovered in North Russia. The IMiomojotera as 



