62 ST. ERTH BEDS. 
The next paper was by Messrs. Kendall and Robert Bell,* who 
by Mr. Wood’s desire had undertaken to carry on the work after 
his death. These authors added largely to the fauna of the 
deposit, giving a list of 72 species of mollusca, and observing that 
20 more seemed to be unknown either in a recent or fossil state. 
They also mention the occurrence of numerous other inverte¬ 
brates, including four species of Bryozoa (all Coralline Crag 
forms), a Balanus, several species of swimming crabs, Echini, 
Annelids, calcareous Sponges, an Alcyonarian, plates of Holo- 
thurias, and spicules of a Tunicate closely allied to Leptoclinum 
tenue. The authors analyse the list of Mollusca, and come to 
the conclusion that the deposit is of about the age of the earlier 
portion of the Red Crag; but to account for the absence at St. 
Erth of the Boreal species which give so marked a character to 
even the oldest part of the Red Crag, they are obliged to postu¬ 
late a land-barrier across the Atlantic from Scotland to Green¬ 
land, thus cutting off in Pliocene times the Arctic seas from any 
communication with the seas of the west of England. The Red 
Crag area is considered to have been at the same period freely 
open towards the north. 
This view of the comparatively recent age of the strata does 
not seem to be borne out by the evidence of the Mollusca. I 
think, moreover, that we should be cautious before raising barriers 
across the Atlantic to account for the undoubted great difference 
between the climatic conditions under which the St. Erth Beds 
and the Red Crag were respectively deposited. 
The next note on the subject occurred in an article published 
during the same year (1886)t, wherein after a study of the 
deposits at Lenham, and St. Erth, as well as the older Crags of 
Suffolk and Belgium, I concluded that they were all of approxi¬ 
mately the same age, but did not deal with the St. Erth fauna, 
except to suggest that it points to a considerable depth of water. 
At the Manchester meeting of the British Association the late 
R. G. BellJ read a short additional note giving some further 
particulars and criticising my conclusions as to the depth of water 
shown by the clays. He observed that the majority of the Mol- 
lusca were such as inhabited the laminarian zone, and did not 
extend to a greater depth than about 15 fathoms. 
Mr. Kendall has since continued his researches into the 
character of the fauna of the St. Erth clays, but at present his 
results are still unpublished, though I believe he has been able 
considerably to add to the lists. 
Messrs. Wood, jun., Kendall, and Robert Bell have had so 
much experience in studying the Mollusca of the Crag that I differ 
from them with the greatest hesitation, especially as I have only 
had an opportunity of examining a portion of the fauna of the St. 
Erth clay. Their list of the Mollusca seems, however, to lead to 
* On the Pliocene Beds of St, Erth. Quart. Journ. Geol. Soc., vol. xlii. pp. 201- 
215. (1886.) 
t On the Pliocene Deposits of North-Western Europe (C. Reid). Nature, 
vol, xxxiv. p. 341. (1886.) 
X The Pliocene Beds of St. Erth, Cornwall. Hep. Brit. Assoc, for 1887, p. 718. 
