GEOLOGia\L EANGE 



271 



elegans and N. variolaria^ and these species also 

 occur in the equivalent beds, the ' Sables Moyens ' 

 of the Paris Tertiary. 



The limestones formed chiefly of nummulites are 

 developed to a large extent on the Continent, and 

 they form a broad but interrupted series extending 

 right across the region of the Old World. In the 

 South of France, at Biarritz, the Nummulitic series 



Fig. 32. — Heterostegixa Limestone ; Tektiary, 

 Wadi Dara, Egypt, x 16. 



is more than 3,000 feet thick. In the South and 

 South-East Alps the Nummulitic limestone series is 

 well developed, and they are associated with Alveolina. 

 In the Northern Apennines the Middle Eocene con- 

 tains Nummulites Biarritzensis, N. Lamarclii, N. 

 Lilcasana, Assilma, Operciilina, and Alveolina ; the 

 Upper Eocene contains Nummulites striata, N. TcJii- 

 hatclieffi, and Orhitoides radians. 



