70 ENVIRONMENT OF VERTEBRATE LIFE, ETC. 



22 species belonging to 3 genera, of which the larger number (17) belong to 

 Etoblattina and others to the genera represented at Cassville by more than a 

 single species. 



'"It is a curious fact, to which I called partial attention when first describing 

 some of them, that these species represent for the most part a distinct group of 

 cockroaches of the genera Etoblattina and Gerablattina, characterized by great 

 length and slenderness of the internomedian area, by a remarkable openness of 

 the neuration in the middle of the tegmina, and by their frequently exceptional 

 length and slenderness. They comprise, indeed, nearly 75 per cent of the species 

 of these two genera at Richmond, and hardly occur elsewhere excepting at Cass- 

 ville, where they compose about 25 per cent of the species of these two genera. 

 The only occurrence of a similar form in Europe is Etoblattina elongata from the 

 lower Dyas of Weissig, Saxony. The occurrence of this type of cockroaches is 

 the characteristic feature of Richmond, and must place this fauna high in the 

 series, as the stratigraphical evidence itself warrants. Its horizon, according to 

 Mr. Huston, who alone has explored the location, is in the barren Coal Measures, 

 a little above the Crinoidal limestone. 



'"It is remarkable that, notwithstanding the close relationship in general 

 features of the two rich faunas of Cassville and Richmond, not a single species 

 has been found common to the two. One species, indeed, I formerly regarded 

 as found in both, but a closer study convinces me that there are in this case two 

 nearly allied forms, and they are accordingly separated in this paper. Further 

 than this, with one or two exceptions, no American species has been found in two 

 different places, and without exception the American species are completely 

 distinct from the European.' 



"Hence we see that not only the reptilian life, but also the insect and plant 

 life of the Conemaugh, supports the conclusion that the beginning of red sedi- 

 ments in the Conemaugh Series marks the dawn of Permian time, while there 

 is nothing in the marine life of the epoch to contradict the same when properly 

 interpreted. The presence of the peculiar type of Odontopteris, like Odontopteris 

 (Lescurites) moorii, in the horizon 20 feet below the great Pittsburgh coal, near 

 Wheeling, West Virginia, as identified by Fontaine, and also in the roof shales 

 of the same near Greensburg, Pennsylvania, also confirms the very late age of 

 the Monongahela series and would thus support the conclusion that the base of 

 the Rothliegende or Dyas should be brought down from the top of the Waynesburg 

 coal to near the base of the Conemaugh series or to the zone of the first appearance 

 of red sediments in that series where there appears to be a true unconformity, 

 or rather disconformity." 



As early as 1880 the significance of the changes shown in the Monongahela 

 deposits was recognized by Fontaine and White, 1 who say in their report 

 on the Permian flora: 



"We may next inquire whether we have evidence of any considerable change 

 which would suffice to produce an important effect, and alter the conditions 

 which prevailed in the lower beds, which all recognize as of Carboniferous age. 

 For this purpose we must turn to the general geology of the district. From this 

 we find, after ascending above the Pittsburgh coal and its associated coals, the 



1 Fontaine, W. M., and I. C. White, The Permian or Upper Carboniferous Flora of West 

 Virginia and Southwestern Pennsylvania, Second Geological Survey of Pennsylvania, 

 Report of Progress PP, p. 117, 1880. 



