IN THE MUD OF THE LEVANT. 97 



acquainted, that exhibits the slightest resem- 

 blance, is furnished by M. Ehrenberg, in his 

 examination of materials brought home from the 

 South Pole, by Dr. Hooker. Some pancake ice, 

 obtained in lat. 78°10' W. long. 162% when melted, 

 furnished seventy- nine species of organisms, of 

 which only four were calcareous Polythalamia, 

 the remainder being all siliceous.* But even 

 this example, remarkable as it is, does not supply 

 us with any real parallelism. The deposits in 

 question have never yet exhibited a single example 

 of a calcareous organism. In reply to my query, as 

 to whether there were any local geological pheno- 

 mena incompatible with the view I entertained. 

 Dr. Bailey observes, " There can be little doubt 

 but that the Polythalamia have been removed from 

 our marine tertiary Infusorial beds, by some 

 chemical action, which action has also attacked 

 the large mollusks, so as to leave only the casts 

 of their shells. Wherever the mollusks are pre- 

 served, there are the Polythalamia also." This 

 is most confirmatory. We may then safely 

 conceive that an analogous change has been 

 effected in the Bermuda deposit, where also 



* Ehrenberg on Microscopic life at the South Pole. Annals 

 Nat. Hist. Vol. xiv. 



