424 



LOWER DEVONIAN. 



[Ch. XXVI 



Fig. 561. 



Fig. 562 



Restored outline of head of Brontes 

 JlabeUifer 



Brontes flooellifer, Goldf Eifel; also S. Devon. 



6tone," or " Eifel Limestone" of Germany, several remains i. Coccosteus 

 and other ichthyolites have been detected, and they serve, as Sir R. Mur- 

 chison observes (Siluria, p. 



l. 



Fig. 563. 



Calceola sandallna, Lam. Eifel ; also South Devon. 

 a. Ventral valve. 5. Inner side of dorsal valve. 



371), to identify the rock 

 with the Old Red Sandstone 

 of Britain and Russia. 



Beneath the great Eifel 

 Limestone (the principal 

 type of " the Devonian" on 

 the Continent), lie certain 

 schists called by German 

 writers " Calceola-schiefer," because they contain in abundance a fossil 

 brachiopod of veiy curious structure, Calceola sandalina (fig. 563). 



Lower Devonian. 

 Beneath the Middle Devonian limestones and schists already enumera- 

 ted, a series of slaty beds and quartzose sandstones, the latter constituting 

 the " Older Rhenish Greywacke" of Roemer, and the " Spirifer sandstone" 

 of Sandberger, are exhibited between Coblentz and Caub.* A portion of 

 these rocks on the Rhine and in some of the adjacent countries were re- 

 garded as 4 Upper Silurian" by Prof. Sedgwick and Sir R. Murchison in 

 1839, but tueir true age has since been determined. Their equivalents 

 are found in England in the sandstones and slates of the North Foreland 

 and Linton in Devon (No. 4 and 5 of the section, p. 420), and, ac- 

 cording to Mr. Salter, in the sandstone of Torbay in South Devon, 

 where many of the characteristic Rhenish fossils are met with. The 

 broad-wiDged Spirifers 

 which distinguish the 

 " Spirifer-sandstein" of 

 Germany have their rep- 



resentatives in the De- 

 vonian strata of North 



America (see fig. 564). Spirifer mucronatus, HalL Devonian of Pennsylvania. 



* Murchison's Siluria, p. 368. 



