Ch. XVn.] FOSSILS OF UPPER CRETACEOUS ROCKS. 



325 



white chalk of England and France there are no proofs of sand, 

 shingle, and clay having been accumulated contemporaneously even 

 in European seas. The siliceous sandstone, called " upper quader " 

 by the Germans, overlies white argillaceous chalk or " planer-kalk," 

 a deposit resembling in composition and organic remains the chalk 

 marl of the English series. This sandstone contains as many fossil shells 

 common to our white chalk as could be expected in a sea-bottom 

 formed of such different materials. It sometimes attains a thickness 

 of 600 feet, and, by its jointed structure and vertical precipices, plays 

 a conspicuous part in the picturesque scenery of Saxon Switzerland, 

 near Dresden. 



FOSSILS OF THE UPPER CRETACEOUS ROCKS. 



Among the fossils of the white chalk, echinoderms are very numer- 

 ous ; and some of the genera, like Ananchytes (see fig. 287), are ex- 

 Fig. 2S7. 



Ananchytes ovata. White chalk, tipper and lower. 

 a. Side view. 



5. Bottom of the shell on which both the oral and anal apertures are placed ; 

 the anal being more round, and at the smaller end. 



clusively cretaceous. Among the Crinoidea, the Marsupite (fig. 294) 

 is a characteristic genus. Among the mollusca, the cephalopoda, or 



Fig. 238. 



Fig. 239. 



3ficrastcr cor-anguinum. 

 White chalk. 



Galerites aJiogalerus, Lam. 

 White chalk. 



Fig. 200. 



a. Belemnites mucronatux. Syn. i? \ucroriata. 



&. Same, showing internal structure. Maestricbt. Faxoe, and white chalk. 



