Masterpieces of Science 



many of the genera and nearly all the species 

 were extinct, to those in which scarcely a single 

 species flourished, which we do not know to exist 

 at present. Dr. A. Philippi, indeed, after an 

 elaborate comparison of the fossil te.rtiary shells 

 of Sicily with those now living in the Mediter- 

 ranean, announced, as the result of his examina- 

 tion, that there are strata in that island which 

 attest a very gradual passage from a period when 

 only thirteen in a hundred of the shells were like 

 the species now living in the sea, to an era when 

 the recent species had attained a proportion of 

 ninety-five in a hundred. There is, therefore, 

 evidence, he says, in Sicily of this revolution in 

 the animate world having been effected "without 

 the intervention of any convulsion or abrupt 

 changes, certain species having from time to time 

 died out, and others having been introduced, 

 until at length the existing fauna was elabor- 

 ated." 



In no part of Europe is the absence of all signs 

 of man or his works, in strata of comparatively 

 modern date, more striking than in Sicily. In 

 the central parts of that island we observe a lofty 

 table-land and hills, sometimes rising to the 

 height of 3,000 feet, capped with a limestone, in 

 which from 70 to 85 per cent, of the fossil testa- 

 cea are specifically identical with those now in- 

 habiting the Mediterranean. These calcareous 

 [chalky or lime bearing] and other argillaceous 

 [clayey] strata of the same age are intersected by 

 deep valleys which appear to have been gradually 

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