T1IK .irilAssir S VST KM 



451 



Coralliun 



Oxford 

 Clay 



by 60 feet of white sandstone ; Cardioceras cardalum, 



0. excavatum, Trigonia conilliiut . . . . ? 150 

 White sandstones with bauds of lignite and occasional 



layers containing casts of marine slu-lls : u.-tuarine 



beds 400 



Wliiie cherty sandstones with many fossils, Aspidoceras 



perarmatum, Perisphinctes achilles, etc. ... 25 

 S ntily clays and black shales with SelemnitesOweni, Bel. 



hastatus, Cardioccran ornatum, Cosmoceras Duncani . 300 

 Sandy shales, with Nucula nuda, Kepplerites yower- 



ianus, and Kepplerites calloviensis .... 5 

 I Calcareous sandstone with many fossils, fauna of Kel- 

 \. la ways Rock 5 



E. CONTINENTAL EQUIVALENTS 



1. Northern and Eastern France 



In the great Parisian basin the general facies of the Upper 

 Jurassic Series i.s similar to that of England, except that it is more, 

 calcareous It can be divided into a similar series of zones and 

 sub-stages, but unfortunately the original English divisions were 

 not founded on zones but on local lithological differences, and 

 though the English names have been widely adopted on tin- 

 Continent, they have become attached to groups of strata which do 

 not exactly correspond with the English divisions. 



Some adjustments of nomenclature will be required on both 

 sides of the Channel in order to bring the names of the several 

 stages into accord. Thus French geologists have created two 

 stages, a Callovian and an Orfordian, but the latter is the zone of 

 Aspidoceras perarmatum and equivalent to the Lower Corallian of 

 England ; while the Callovian includes the ornatum clays, though 

 these have since been separated as a sub-stage under the name of 

 Divesian. Thus their Callovian is practically our Oxfordian. 



Again there has been much confusion about the correlation of 

 the equivalents of the Corallian and Kimeridge Clay in France, 

 for the beds which represent our Upper Calcareous Grit are known 

 as the Astartian or, Sequanian, and have been classed in some 

 places with the Corallian and in others with the Kimeridgian 

 linn tones. De Lapparent, following Tombeck, dropped the name 

 Corallian altogether, and advocated an expanded Sequanian as its 

 substitute; but Messrs. .1. F. Blake and T. Roberts, who both 

 carefully studied the Upper Jurassic Series of Eastern France and 

 the Jura, agree in thinking that the Astartian is more closely 

 allied to the Kimeridgian than to the Corallian.- 4 



On the other hand, they agree that the English Kimeridge 



