50 PERMIAN ERA. 



some instances many yards, and in a few, several hundred 

 feet, removed from the corresponding ends of neighbouring 

 fragments. These are held to be results of volcanic move- 

 ments below, the operation of which is further seen in nume- 

 rous upbursts and intrusions of fire-born rock, (trap.) That 

 these disturbances took place about the close of the formation, 

 and not later, is shown in the fact of the next higher group of 

 strata being comparatively undisturbed. Other symptoms of 

 this time of violence are seen in the beds of conglomerate 

 which occur amongst the first strata above the coal. These, 

 as usual, consist of fragments of the elder rocks, more or less 

 worn from being tumbled about in agitated water, and laid 

 down in a mud paste, afterwards hardened. ( 30 ) It is to be 

 admitted for strict truth, that in some parts of Europe the 

 carboniferous formation is followed by superior deposits, 

 without the appearance of such disturbances between their 

 respective periods; but such cases apparently are exceptive. 



PERMIAN ERA. FIRST TRACES OF REPTILES. 



IN this subordinate manner, may be noticed a short series of 

 strata, following, whether conformably or otherwise, upon the 

 carboniferous formation, and to which a general name has 

 been applied, from its being unusually well developed in the 

 portion of Russia which formed the ancient kingdom of 

 Permia. This sub-formation comprehending in ascending 

 order a group of sandstones, called with us the Lower New 

 Red Sandstones, and amongst the Germans Rothe-todte- 

 liegende ( 31 ) a thick calcareous bed called with us the 

 Magnesian Limestone, by the Germans Zechstein, and some 

 other strata is, in respect of fossils, a continuation of the 

 carboniferous system. With it, however, ends a range of 

 animal forms which first appeared in the Silurians, and passed, 

 with the changes which have been indicated, through the 

 Devonian and Carbonigenous eras. 



