i64 C O N C H O L O G ¥• 



found foffil, with many other fuch pa- 

 rallel inftances. 



The foffil Ammonia, or Ammonitae, 

 are found in great abundance, and of ma- 

 ny fpecies, in moft parts of the world ; 

 from the fmall fize of a pea, through 

 all the gradations of fizes, to above a 

 yard in diameter, and proportionably thick. 

 Thefe are not objeds that efcape the eye 

 by their minutenefs ; yet, neverthelefs, all 

 the fpecies of them ftill remain to be dif- 

 covered, except one very minvUe kind. 



This difcovered living fpecies of Ammo- 

 nis is fo very minute, as hardly to exceed 

 the bignefs of a turnep feed, and does not 

 weigh the hundredth part of a grain ; 

 therefore demands the aid of the micro- 

 fcope to view it. It was found by Plan- 

 cus with the recent Orthoceroses above- 

 mentioned in the fea fediment at Rimini : 

 he has defcribed and figured it in his 



work. 



