INTRODUCTION. xxiii 



represented by the Kartinsk Goniatites Orhignyanus and G. Kingianus. Both 

 genera occur in the (?) Triassic Marls of St. Kassian ; so that there is httle doubt 

 they will yet be found in strata of the Permian period. The family Nantilidce has 

 only two or three generic representatives in the present rocks. The two species of 

 Nautilus are interesting, as having a striking resemblance to the Carboniferous Nautilus 

 clitellarius and N. concavus. One of the Permian species, N Schlotkeimi, is found both 

 in England and Germany ; but N. Bowerbankianus has only yet been found in the 

 former country. Dr. Geinitz has figured in the ' Versteinerungen' a so-called 

 OrtJioceratites, said to have been found in the Kupfer-schiefer of Ilmenau, — a statement 

 which may be received with very little doubt, if it be correct, that a congeneric species 

 ( Orthoceros Freieslebeni) occurs in the Triassic Marls of St. Kassian. M. de Verneuil 

 has found a portion of a Cyrtoceros in the limestone (Permian) of Schidrova near 

 Ustvaga.i 



Fishes appear to have been tolerably abundant in the Permian Ocean : they belong 

 exclusively to the Placoid and Goniolepidot orders — great groups, which, during the 

 Protozoic period were the sole representatives of their class. The order Placoidei is 

 scarce in our home deposits, — Gyracanthus formosus being the only example found in 

 England, and Gyropristis obliquus the only one found in Ireland ; five or six, however, 

 have been determined by Count Milnster to characterise the Mergerl-schiefer of 

 Riechelsdorf. The order Goniolepidoii is better represented. Fishes appear to have been 

 decidedly more local in their habitats than any of the other Permian classes noticed ; 

 for it is doubtful if any of the species occurring in Germany have yet been found 

 in England. It requires to be observed, however, that Dr. Geinitz has recorded the oc- 

 currence of the English species PalcBoniscus elegans, P. glaphyrus, and P. macropthalmus, 

 in the German Kupfer-schiefer : Paleeoniscus Freieslebeni — a German Permian species, 

 is stated to have been found in the Carboniferous rocks of Ardwick in Lancashire ; and 

 M. de Verneuil records the occurrence in Russia of the German species Palaoniscus 

 lepidurus, and P. Vraiislaviensis : but these instances require a further investigation. 

 None of the genera of fishes, with the exception of Miinster's Placoids, found in the 

 Permian system, can be strictly said to be essentially characteristic of it ; as Pygoptems, 

 Palaoniscus, Coela'canthus, and Platysomus, also characterise (and perhaps to the same 

 extent) the Carboniferous system. While the genus Palceoniscus takes us into the 

 Protozoic system, Platysomus, by its relation to Pycnodus, carries us imperceptibly into 

 the Deuterozoic : this fact, as will hereafter be seen, has an important bearing on the 

 question under consideration. 



Class Beptilia. Until the important discovery within the last two or three years 



of Archigosaurus Decheni, in the Coal-measures of Saarbruck, the Permian period was 



considered to have been the first that witnessed the creation of air-breathing animals. 



However much such a discovery may have diminished the interest attached to the reptilian 



^ Vide Note sur les Equivalents du Systfeme Permien en Europe, p. 12. 



