PLATE XV. 



1". h, c, and d. Ammonites Sussexiensis ; a specimen given me by Dr. Mantel], from the 

 Grey Chalk near Lewes ; reduced to two thirds its natural diameter. 



'la, b, and r. Ammonites Cunningtoni ; from a specimen belonging to T. A. Falkner. 

 Esq., of Manningford, reduced to two thirds its natural diameter; from 

 the Grey Chalk of Upton Scudamore, near Warminster. 



