1813.]. On Formaimis, ' ^195 



places were inhabited 3 probably even after tlie erection of the 

 neighbouring churches and cloisters. Similar depositions take 

 place at this day in limestone countries where calcareous tulf is 

 formed; and it is well known that in the Travertine. rock of 

 Rome, a formation of the latest period, we find leaves, Sec. of 

 the various trees which now grow in the adjacent country. This 

 very probable opinion of Von Buch's is founded, on the excellent 

 description of ^Eningen, published by Dr. Karg, of Constance^ 

 which contains the first accurate view of the country of 

 ^ningen. 



The petrifactions are contained in a slaty limestone of loose 

 texture. It extends about a mile in length, and fills a hollow in 

 the limestone rocks, and not a trace of it is to be seen in the 

 neighbouring country. The valley appears to have emptied itself 

 at no very remote period, and left exposed at its bottom the lime- 

 stone slate of ^ningen. 



Dr. Karg gives an accurate and interesting systematic cata- 

 logue of all the petrifactions hitherto found in this limestone^ 

 and shows how observers have been deceived, particularly whea 

 they imagined that they had before them American and Indian^ 

 even entirely unknown organic forms; and declares, after a 

 careful and accurate examination of many hundred petrifactions, 

 that he is not inclined to consider any of them as exotic. In- 

 deed, we cannot but consider this opinion as well founded, when 

 we attend to the many remarkable histories given by Dr. Karg of 

 iEningen petrifactions. Thus Scheuchzer's Homo diluvii testis 

 which probably lived at a later period than the building of the 

 neighbouring cloisters of Petershausen, even during Scheuchzer^s 

 life-time, was by himself admitted to be but a quadruped. An 

 exotic porpoise, under the hands of Dr. Karg, proved to be 

 the common pole-cat ; and the shoots and leaves of the vine, 

 which Walch describes as occurring in this limestone, prove 

 to be nothing more than branches of the black poplan 

 Among the great number of bivalve shells that occur in the 

 slate of Mnmger\, Dr. Karg did not find a single species 

 of marine origin ; all were of fresh water growth. He also found 

 that all the roots, woods, and leaves, that are inclosed in this 

 rock, belong to some of the vegetable species that now grow m 

 the vicinity. He found very distinct specimens of the brancheSj 

 leaves, and nuts of the walnut tree (Joglans Regia), But it is 

 said that the walnut tree was imported from Armenia into Italy^ 

 and from thence distributed over Germany. This interesting 

 fact, Von Bach remarks, leads us very near to the period wht;n 

 the Mmngen petrifactions took place, and renders it probable 

 that the formation is of very recent date. 



What then can we deduce from the emptying of a lake, and 

 the operations that took place at its bottom, in regard to the 



