ZONE OF AEGOCERAS ANGULATUM. 



31 



organic remains and an accurate determination of the species, each of these authors has 

 placed the strata of the Lower and Middle Lias in their proper zones. Similar sthdies 

 had been well and carefully carried out by previous observers with like results, as 

 Bornemann, Strombeck, Ulrich, Ewald, RoUe, Wagener, &c., and from the united 

 Palseontological data thus obtained we have learned the correlation of the north-west 

 German Lias beds, as shown in the following table — 



The Middle and Lower Lias of North Germany. 



Von Sbebach. 



SCHLONBACH. 



Emerson. 





MIDDLE LIAS. 





Amaltheenthone. 



Zone of Am spinatus. 



Beds with Am. spinatus. 



Upper zone of Am. margaritatus. 



Absent. 



Beds with 

 Am. capricornus. 



Upper zone of Am.Jimbriatus. 

 Lower zone of Am. margaritatus. 



Absent. 



Beds with 

 Am. brevispina. 



Lower zone of Am. fimbriatus. 



Beds with Am. centaurus. 



Zone of Am. Jamesoni. 



Beds with Am. brevispina. 



Beds with Terebratida subovoides 

 and A7n. armatiis. 





LOWER LIAS. 





Beds with A^n. planicosta. 



Zone of Am. planicosta. 



Beds with Am. bifer. 



Beds with Am. planicosta. 



Arietenschichten. 



Zone of Am. geometricus. 



Beds with Am. geometricus. 



Zone of Am. BucJclandi. 



Absent. 



Angulatenschichten. 



Zone of Atn. angulatus. 



Beds with Am. angulatus. 



Psilonotenschichten. 



Zone of Am. Johnstoni. 



Psilonotenschicht en. 



Rheetic. 



Zone of Avicula contorta. 



Avicnla. 



