putridity in the absence of oxygen? 



What influence has the sediment in the destruction? Does a single organ- 

 ism die, or when and where have whole biocoenoses been destroyed? 



Do the skeletons stay in place or are they transported, and if so, where ? 



How are the shells heaped up, and what quantities are necessary to form 

 a rock with mineral oil? 



2. The behavior of t he life, formed as tracks and trails in the sediment. 



The organism forms a document of its existence in the sediment in two 

 ways: 



a) as a body with its skeleton. 



b) as tracks and trails of a distinct behavior. 



Ichnology today is an important discipline, and many a rock shows its sub- 

 marine formation only by tracks and trails made by organisms in the sediment. 

 Particularly in this case a fundamental knowledge of the recent is the suppos- 

 ition for the interpretation of the fossil. We recognized this very late, and all 

 the gaps in our knowledge are larger as a result. 



Today we speak of "fos si -textures" or "fossi-structures" of bedded rock, 

 and we mean the texture or structure marked by boring animals and the changes 

 which the beds have undergone because of the activity of the endobionts in the 

 bottom. These changes can be figurative or may only deform the beds. The 

 study of the endobionts is more important than the trails made on the surface 

 of the sediment. 



3. Animals and communities of animals such as fossils of a facies. 



Ecological research has for a long time shown the close relation between 

 the animals and their communities and that a determinate community of ani- 

 mals always points to a determinate environment. Thus we are also able in 

 fossil cases to determine a part of a rock as a unity, and we are able to delimit 

 it from another space of life which existed at the same time in the past. 



The geologist and the paleontologist speak of the "facies", and they mean 

 it to be an epoch of the same conditions, the epoch not only delimited by the 

 character of the sediments but also by a community of organisms which is 

 called a "biofacies". The laws of facies and of its changing in sediments and 

 animals can only be studied on recent sea bottoms. The phenomenon must be 

 examined in its entire scope of time and space. 



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