8 
NODULE BEDS. 
Owen as to the Cetotolites having been derived from the London 
Clay, thinking that they more probably came from the Coralline 
Crag, or some other deposit of newer Tertiary age. Most of 
the fish-teeth might, in his opinion, have come from the London 
Clay, as well as some shells and many Crustacea; there being 
few Secondary fossils. He believed, therefore, that the Red 
Crag sea was chiefly bounded by London Clay land, the fossils 
from which were introduced into the Crag by coast-action. The 
sandstone nodules, mixed with the phosphatic nodules, some of 
which contain casts of shells, he regarded as of older Crag age, 
though there is no similar material in our existing Coralline Crag. 
The Red Crag might thus include the harder fragments of various 
Tertiary beds. This paper concludes with a list of the derived 
fossils. 
In 1865 Prof. E. R. Lankester* treated of the sources of the 
mammalian fossils. He considered that the derivative fossils can 
be distinguished by their greater density and mineralization, that 
in the Nodule Bed not one fauna, but a mixture or selection from 
several, belonging to Pliocene, Miocene, and Eocene strata may 
be recognised; that the Cetacean bones were derived from some 
deposit of the age of the Middle Crag of Antwerp, which con¬ 
tains similar species in an unworn state; and that certain of 
the land mammals come from a Miocene bed; while Hyraco^ 
theriiim, Coryphodon, and many of the sharks point to Eocene strata. 
The same author in 1867,t referring to the suggested correla¬ 
tion of the Coralline Crag with the Black Crag of Belgium, asked, 
if this be the case, how the occurrence of the remanie teeth of 
similar sharks and Cetacea in both oF our Crags to be accounted 
for, since no unworn specimens occur in our Coralline Crag, as 
they do in the Black Crag, whence, he asked, came the abundant 
derivative Cetacean and shark fauna of our Red Crag. He 
reiterated his conclusion that the Black Crag is an older deposit 
of the Crag sea, which had its representative in Suflblk, and 
from which first the Coralline and then the Red Crag derived 
their sharks’ teeth and Cetacean bones. 
In 1868 Prof. LankesterJ, reverting to his published opinions, 
especially as to the derivation of the bones of the coprolite- 
bed ” from Diestian deposits, noted the finding of 30 or more 
species of molluscs in the sandstone-blocks (box-stones) which 
seem to be Diestian, and of the largest Carcharodon toqth he 
had seen. He regarded the coprolite-bed ” as a littoral 
accumulation, formed, just before the Coralline Crag, from the 
detritus of London Clay and Diestian strata, with fragments of 
subaerial and freshwater accumulations (whence its Mastodon, 
Rhinoceros, Tapir, Hyaena, Sus, and Cervus teeth). He objected 
to the name “ coprolite-bed,” because there is probably not one 
coprolite in it, the nodules being masses of London Clay which 
* Quart. Journ, Geol. Soc., vol. xxi. pp. 221-226. 
f Geol. Mag., vol. iv. pp. 91-92. 
J Ibid., vol. V. pp. 254-258. 
