E. H. Sellards — Types of Permian Insects. 173 



the occurrence of true ephemerids. The Russian deposits have 

 also yielded forms regarded as representing Paleohemiptera 

 and Mantoidse.* These last two groups have not been recog- 

 nized in the Kansas Permian. The presence of the ephemerids, 

 however, forms a strong tie in common between the insects of 

 the Russian and the Kansas Permian. 



The insects of the Wellington are on the average of small 

 size as compared with Coal Measure insects. This is particu- 

 larly noticeable among the cockroaches, all of which are small. 

 This dwarfing of the fauna is of interest as probably indicat- 

 ing unfavorable climatic conditions. 



The Geological Relations of the Associated Plants. 



Plants, as previously stated, are associated with the insects 

 at the Banner City locality. A paper describing the plants 

 from this horizon is being published by the Kansas Geo- 

 logical Survey. In the writer's opinion, the plant fossils 

 indicate unequivocally the Permian age of the formation from 

 which they come, The evidence as to the age of the Wel- 

 lington shales, derived from the flora, is thus summarized in 

 the report referred to ; "More than two-thirds of the Welling- 

 ton species are either identical with or most closely related to 

 species or genera characteristic of the European Permian. 

 The points which seem to have the most importance as 

 bearing on correlation of the Wellington are the following : 



(1) The complete absence from the Wellington of species in 

 any way confined to or distinctive of the Coal Measures. 



(2) The comparatively small number of species originating as 

 early as Upper Coal Measure time. (3) The presence of a 

 few species common to and characteristic of the Permian of 

 Europe. (4) The close relation of the new forms to species 

 characteristic of the European Permian. (5) The distinctly 

 Permian facies of the flora as a whole and its marked advance 

 over the flora of the Upper Coal Measures. 



The advance in the flora consists in the number of species 

 and in the abundance of individuals of callipterid and tseniop- 

 terid ferns, and of the new fern genus, Glenopteris, which 

 appears to be related, on the one hand, to callipterid ferns of 

 Permian types, and, on the other, to the Triassic genera 

 Cycadopteris and Lomatojpteris. 



The evidence derived from the fossil plants as a whole 

 seems to assure the reference of the Wellington to the true 

 Permian in the European sense." 



This conclusion drawn from the plant fossils is now fully 

 confirmed by the evidence derived from the insects. 



* Die Fossilen Insekten, 348, 1906. 



