INTRODUCTION. XX 
represented by the Kartinsk Goniatites Orbignyanus and G. Kingianus. Both 
genera occur in the (?) Triassic Marls of St. Kassian; so that there is little doubt 
they will yet be found in strata of the Permian period. The family Nautihde has 
only two or three generic representatives in the present rocks. The two species of 
Nautilus are interesting, as having astriking resemblance to the Carboniferous Mautilus 
clitellarius and JV. concavus. One of the Permian species, JV. Schlothevm, is found both 
in England and Germany; but JV. Bowerbankianus has only yet been found in the 
former country. Dr. Geinitz has figured in the ‘ Versteinerungen’ a so-called 
Orthoceratites, said to have been found in the Kupfer-schiefer of IImenau,—a statement 
which may be received with very little doubt, if it be correct, that a congeneric species 
(Orthoceros Freveslebent) 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.} 
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 Miinster to characterise the Mergerl-schiefer of 
Riechelsdorf. The order Gonzolepidot: 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 Palgoniscus elegans, P. glaphyrus, and P. macropthalmus, 
in the German Kupfer-schiefer: Paleoniscus Freieslebeni—a German Permian species, 
ig 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 Palconiscus 
lepidurus, and P. Vratislaviensis: 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 Pygopterus, 
Palaoniscus, Celacanthus, and Platysomus, also characterise (and perhaps to the same 
extent) the Carboniferous system. While the genus Palzoniscus 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 Reptilia. Until the important discovery within the last two or three years 
of Archigosaurus Dechent, i 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 
1 Vide Note sur les Equivalents du Systeme Permien en Europe, p. 12. 
