ST. AGNES BEACON, 
67 
clay mentioned by De la Beebe, but should it be again exposed 
it would be advisable to wash the middle and lower portions for 
microscopic fossils. 
Standing on this old beach of St. Agnes Beacon, one looks 
across a lower undulating country, out of which rise here and 
there bold hills or masses of high land with more rugged outlines. 
With this smoothed undulating plain lying at one’s feet it is difficult 
to avoid the conclusion that it was formerly the bed of the sea, 
and that the distant hills rose, like St. Agnes Beacon, above the 
seadevel, converting Cornwall into an archipelago somewhat 
resembling the Scilly Islands at the present day. What may have 
been the date of this ancient submergence is difficult to prove 
in the absence of fossils ; but we are unacquainted with any period 
to which it can belong unless it correspond with that during which 
the fossiliferous clays of St. Erth were being laid down. We 
may therefore provisionally refer the deposition of the strata at 
St. Agnes Beacon and some of the general sculpture of the surface 
in this part of Cornwall to the Older Pliocene period. 
Crossing the Channel into Normandy, one finds in the low- 
lying peninsula of Cotentin small outliers of Upper Tertiary 
strata of different ages, resting on various rocks, from Devonian 
to Cretaceous. These have been thoroughly examined by 
M. G. Dollfus."^ They are important as helping to show the re-* 
lation of the Pliocene strata of England to those of the Continent, 
and also to the Faluns of the Loire ; but Pliocene beds occupy 
almost as small an area in the north of France as they do in the 
south of England, and we need much more evidence before the 
minor divisions of deposits varying so greatly in character can be 
satisfactorily correlated. 
The upper Tertiaries of Cotentin are thus divided by M. 
Dollfus :— 
Pliocene / ^ Nassa de Saint-Martin d’Aubigny. 
Oonglomerat a Terebratules de Saint-Greorges-de-Bobon. 
Miocene Falun a Bryozoaires de Saint-Eny. 
The Faluns are about 25 feet thick, and consist of soft cal¬ 
careous strata, formed almost entirely of much-worn fossils— 
Bryozoa, Corals, Mollusca, and Echinids. The actual shell in 
both Gasteropods and Lamellibranchs has always disappeared. 
In lithological character this deposit resembles the Coralline 
Crag, and it contains also a similar fauna, though several of the 
species mentioned by M. Dollfus have not been found in England. 
On palaeontological grounds M. Dollfus correlates the Faluns of 
Cotentin with the Miocene Faluns of the Loire ; the areas are, 
however, widely separated, and the list of fossils is not yet very 
large. 
The next deposit—the conglomerate with Terehratula grandis 
—appears to rest on an eroded surface of the underlying 
* Esquisse des Terrains Tertiaires de la Normandie. Mem. Soc. Geol. Normandie 
sur I’Exposition Geol. du Havre, en 1877, p. 478. 
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