540 



MIDDLE DEVONIAN. 



Fig. 610. 



Megalodon ciwullatus, Sow. Eifel; also Bradley, 

 S. Devon. 



a. The valves united. 



b. Interior of valve, showing the large cardinal tooth. 



Conularia ornata, D'Arch. 



and De Vera. 



(Geol. Trans., Sec. Ser., vol. vi. 



pi. 29.) Eefrath, near Cologne. 



head is seldom found perfect ; a restoration of it lias been attempted 

 by Mr. Salter, (fig. 613). 



Fiaf. 612. 



Fig. 613. 



Restored outline of head of 

 Brontes flabellifer. 



Brontes flabelltfer, Goldf. Eifel ; also S. Devon. 



In this same formation, comprising in it the " Stringocephalus lime- 

 stone," or " Eifel Limestone " of Germany, several remains of Coccosteus 

 and other ichthyolites have been detected, and they serve, as Sir E. 

 Murchison . observes (Siluria, p. 371), to identify the rock with the 



Old Red Sandstone of 

 _______ Mg - m - Britain and Russia. 



Beneath the Eifel Lime- 

 stone (the great central 

 and typical member of 

 "the Devonian" on the 

 Continent) lie certain 

 schists called by German 



Calceola sandaUna, Lam. Eifel; also South Devon. ., ,. .~ , , , . 



a. Ventral valve. b. Inner side of dorsal valve. writers Calceola-SCllie- 



