146 ROMER’S DESCRIPTION OF THE CHALK 
In the preceding synoptical table we meet, beneath the qua- 
der, first, variegated clays, ferruginous sandstones and Luma- 
chellas; then gray argillaceous masses with subordinate marly 
Lumachella; and, finally, light-coloured limestones and bluish 
marls,-~the formation of the so-called “ Spatangus-limestone.” 
This last-mentioned deposit appears to be entirely wanting in 
the North of Germany, as well as the fossil species, Pteroceras 
Pelagi and Spatangus retusus; at least we are not acquainted 
with any calcareous or marly deposit in Germany which can be 
referred to it. Our Hils-clay and Hils-conglomerate must there- 
fore belong to the middle sections of the above table. We 
have nowhere been able to detect a superposition of the one de- 
posit over the other, but if we take into account the general 
character of the fossils, the Hils-clay appears to be the older 
formation. Terebratula latissima, T. depressa, T. nuciformis, 
Pecten asper, P. quinquecostatus, and P. equicostatus, as well as 
Ostrea macroptera, true chalk forms, have not yet been found 
in it ; on the other hand, the Hamites of Heligoland and Speeton 
certainly agree for the most part with those found in the Crimea. 
Ammonites asper likewise appears to belong to the older Neoco- 
mian, and several other Ammonites, e.g. 4. venustus, A. Phil- 
lipsii, A. rotula, exhibit a greater affinity to those of the Jura 
than those of the Hils-conglomerate. 
Under these circumstances we consider ourselves justified in 
considering our Hils-clay as equivalent to the gray schistose 
clays which in France overlie the Spatangus-limestone ; and 
look upon the Hils-conglomerate as parallel to the Lumachellas, 
which are met with there above those gray clays and beneath 
the variegated clays of the chalk-marl. At Salzgitter the con- 
glomerate is subjacent to an argillaceous mass, which is perhaps 
of the same age as the variegated clays. 
It is difficult to prove the correctness of these parallels, till - 
the fossils occurring in the Neocomian in France have been de- 
scribed: it is to be hoped that this will very soon be done. 
Most of the argillaceous masses in the south of England which 
have been described by Fitton, with the inferior portion of the 
lower greensand, as “ Fuller’s-earth,” will undoubtedly prove to 
be equivalents with the Hils-clay. It is scarcely possible that the 
deposit should be absent there, since it has been discovered in 
Yorkshire, in Heligoland and in France. 
Some French geologists are of the opinion that the Weald-clay 
