



SEQUEL TO SYSTEMATIC GEOLOGY. 583 



Villiers, De Beaumont, and Dufrenoy, came to Eng- 

 land in 1822, and following the steps of the best 

 English geologists, in a few months made them- 

 selves acquainted with the English series. They 

 then returned to France, and, starting from the 

 chalk of Paris in various directions, travelled on 

 the lines which carried them over the edges of the 

 strata which emerge from beneath the chalk, iden- 

 tifying, as they could, the strata with their foreign 

 analogues. They thus recognized almost all of the 

 principal beds of the oolitic series of England 7 . At 

 the same time they found differences as well as 

 resemblances. Thus the Portland and Kimmeridge 

 beds of France were found to contain in abundance 

 a certain shell, the gryphcea virgula, which had not 

 before been much remarked in those beds in Eng- 

 land. With regard to the synonyms in Germany, 

 on the other hand, a difference of opinion arose 

 between M. Elie de Beaumont and M. Voltz*, the 

 former considering the Ores de Vosges as the equi- 

 valent of the Rothe todte liegende, which occurs be- 

 neath the Zechstein, while M. Voltz held that it was 

 the lower portion of the Red or Variegated Sand- 

 stone which rests on the Zechstein. 



In the same manner, from the first promulga- 

 tion of the Wernerian system, attempts were made 

 to identify the English with the German members 

 of the geological alphabet ; but it was long before 

 this alphabet was rightly read. Thus the English 



7 De la Beche, Manual, 30">. " II). 381. 



