Report of the State Geologist. 



411 



The Devonian characters of this Hercynian fauna are predominant, 

 and are regarded as indicating not only a Lower-Devonian, but an 

 earliest Devonian age or equivalence. 



In comparing this fauna with that of the upper etages of the 

 Bohemian basin, Kayser found over fifty species, or rather more than 

 twenty-five per-cent of the former, represented in the latter by forms, 

 either identical or closely allied.* 



BARROisf subsequently turned this statement in a somewhat dif- 

 ferent light, by adding that the per-centage would be materially 

 lessened by comparison of the concurrent species with the 2,000 

 species described by Barrande from the Bohemian; in other words, 

 that the proportion was not reduced to a common denominator. 

 Nevertheless, Kayser's deduction of the equivalence of the F, G, H 

 fauna with the Hercynian, is not affected by the reversal of this 

 proposition, as by far the greater number of the Bohemian species, are, 

 as far as yet known, indigenous and not diagnostic. The summary 

 statement of the characters of the Bohemian fauna in question is given 

 substantially as follows : J In spite of many Silurian characters, it 

 bears a pronounced Devonian expression, especially shown in its Goni- 

 atites, numerous Devonian brachiopod types, the absence of all exclu- 

 ively Silurian cephalopod and trilobite genera. The Silurian affinities 

 are indicated primarily by a few Upper-Silurian brachiopods, by Caly- 

 mene and the Graptolites, and secondarily, by numerous Dalmanites§ 

 and Trochocerata. Compared with the Hartz fauna, with numerous and 

 fine Devonian brachiopods and corals (?) the Bohemian fauna possesses 

 more features suggestive of the Silurian. In the extraordinary agree- 

 ment of both faunas, the decisive Devonian character of the Hartz 

 Hercynian exerts its influence on the Bohemian fauna, while the 

 latter, as it affords some doubt of its age when considered by itself, 

 by comparison shows its relation to the Devonian. 



Besides these comparisons with the Bohemian upper faunas, the 

 author elicited points of equivalence with faunas in other regions; 

 those of Thuringia, Franconia and the Fichtel Mts., of the Rhenish 

 provinces, western and southern France, and of North America. 



The propositions enunciated by Kayser in regard to the age and 

 equivalence of his Hercynian fauna, though warmly espoused by the 

 German geologists generally, met with strong opposition on certain 

 issues. 



*Op. cit., p. 254. 



t Faune du Calcaire d'Erbray, p. 299, 1889. 

 t Kayser, p. 262. 



8 We haveelsewhero referred to the fact, now well established, that the predominance 

 of typical Balmanites ( Uaxsmannia) is a most important character of early Devonian 

 faunas. 



