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cum stance that renders it more distinct from A. peramplus 

 than otherwise it would appear. I have an intermediate 

 specimen from Dover, by favour of Mr. Sankey, the 

 aperture of which is elliptical ; and a small one from 

 Lewes, between the two ; both these have the radii 

 distinct, especially the small one, in which they extend 

 nearly to the front ; these specimens lead me to suspect 

 the A. Lewesiensis is only a compressed variety of the 

 peramplus. Mr. Phillips has observed in his paper on 

 the Chalk Cliffs near Dover, (Trans. Geol. Soc. V. 

 p. 30 and 33), that the Ammonites lie horizontally in the 

 Chalk : this may account for their being so frequently 

 compressed : but as Mr. Mantell has had numerous 

 opportunities of observing them, I have followed him in 

 describing them as two species. I have seen one on the 

 beach near Dover that measured full three feet across, 

 but it is so long ago that I do not know which species to 

 refer it to. 



