A. EF. Verrill—The Bermuda Islands; Geology. 
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been covered in some places by a considerable thickness of late 
seolian limestones, as shown in fig. 11. 
Mr. Agassiz, however, took the extreme opposite view, and 
believed that they are all of modern origin, and formed since the 
islands attained their present level. He believed that all the mate- 
rials, even of the most elevated beds, were carried up the beaches by 
the waves and winds, to the heights at which they are now found, 
My own conclusions are intermediate, for I consider them local 
shore and shallow water deposits of different periods. The older 
and higher ones I believe to have been formed at a period when the 
land stood at least 10 to 15 feet lower than now, as explained above. 
Others are still forming. The older ones, especially, are worthy of 
more careful studies. 
Lieut. Nelson, 1840, was the first to describe a genuine beach 
formation with marine fossils, at Bermuda. It seems to have been 
one of the older ones, resting on Pliocene limestone. His descrip- 
tion was as follows : 
“The most interesting organics with which I have met were in 
the rock now inclosed by the North Bastion at Ireland Island. 
Whilst cutting the escarp of this work, a large block of reef was 
discovered in the solid rock fifteen or twenty feet from the surface, 
and at about four feet above high water. This specimen contained 
Meandrina areolata,* the common Mytilus of the coast [| MW. adustus|, 
retaining its black colour, and a pink Millepore { Polytremacis ?] very 
common in the serpuline reefs. This spot, conceiving the truncated 
strata of h*land I. to be restored to their proper form, must have been 
at the very apex of the saddle, and is perfectly distinct from the 
loose, soft, and newer sandstones. Above the level of this spot lie 
the strata, a, a, fig. 8, which for some hundred yards along the 
north side, consist chiefly of a hard subcrystalline limestone.” 
““In the centre of this rock was a cavern ; and entangled amongst 
the stalagmitic lining (as well as in that of other caves and crevices), 
or else lying in heaps in the loose red earth within, we found abund- 
ance of a large and delicate Helix |= Pecilozonites Nelsoni|.” 
This statement regarding the loose red soil and stalagmitic 
materials containing this extinct snail, indicates that the clay and 
underlying rock belonged to the Walsingham formation, for the 
* This specimen, which is still preserved in London, has been recently iden- 
tified as Mycetophyllia Lamarckana by Gregory. I have referred this species to 
Mussa (these Trans., xi, p. 68, note). If correctly named by Gregory, it is not 
known to inhabit Bermuda at this time. 
Trans. Conn. Acap., Vou. XII. 6 Jung, 1905. 
