THE PRE-ADAMITE EARTH. 



case. The body is covered with scales, those of the head being 

 highly ornamented. 



The Pterichthys takes its name from two wings or lateral 

 appendages, which, like the spines of the common bull-head, 

 were weapons of defence. The head and fore part of the body 

 are protected by large angular escutcheons two eyes are placed 

 in front of the lateral spines. The species of these which occur 

 in the British strata are from eight to ten inches in length, but 

 specimens of still greater length were found in Russia by Sir R. 

 Murchison. 



Triassic Age. 



308. Above the Palaeozoic formation a group of strata has been 

 deposited, called the Triassic formation (47), consisting of the new 

 red sandstone, muschelkalk, and variegated marls, or marnes 

 irisees of the French. This formation has been generally con- 

 sidered as consisting of three stages. A scrupulous analysis of 

 its composition, as well with relation to its fossils as to the condi- 

 tions of its stratification, shows that, between the sandstone and the 

 muschelkalk, there is no real distinction either geological or zoolo- 

 gical. We shall, therefore, here, following D'Orbigny, consider the 

 Triassic formation as consisting of two stages only ; the first, or 

 lower, called the Conchiferous ; and the second, or upper, the 

 Saliferous, from the prevalence of salt-mines in it ; such, for ex- 

 ample, as those of Salins, Lons-le-Saulnier, and Salzbourg. 



309. The configuration of the land in this, as in the former age, 

 is traced bj- observing the outlines of the strata, and the distinc- 

 tion of their organic remains. The convulsion which elevated the 

 system of the Rhine (213) produced a general deluge, which de- 

 vastated the earth, destroying altogether the vegetation which 

 clothed it, and the races which peopled it in the last period of the 

 preceding age. When the seas had retired to their new beds, and 

 tranquillity was re-established, the outlines of land and water were 

 defined. A great island seems then to have extended from the 

 west of England across France to Austria, including Brittany, the 

 Limousin, and Forez, throwing out two peninsulas, one towards the 

 Pyrenees, and the other across the province of Burgundy (fig. 146). 



Another island coincided in position with Belgium, throwing 

 out a peninsula to the south, which extended over the Yosges and 

 the Grand Duchy of Baden, its direction being parallel to the 

 range of the Black Forest. The land previously uncovered in 

 England, extending from Cornwall through Wales to Cumberland, 

 was probably increased by a large surface, extending from Derby- 

 shire to Durham. With these exceptions, the land seems to have 

 remained generally as it was in the Carboniferous and Permian 

 60 



