72 A, E. Verrill—The Bermuda Islands; Geology. 
numbers of P. Nelsoni.* On Tucker’s Island, in Great Sound, it 
contains a large cavern, supported by great stalactitic columns, and 
with several feet of sea water over its floor. I observed the red- 
clay and stalactitic breccia, containing the Nelson’s snail, in the 
ledge near its entrance, and in other places on the island. 
It has also been recorded as occurring on St. George’s Island. I 
did not find the extinct snails in that vicinity, but had little time to 
search for them there. 
Professor Rice, however, described a very hard limestone, of 
geolian origin and containing fossil land snails, as occurring at the 
old quarry at Stocks Point. It was overlaid by a local deposit of 
beach rock, containing many marine shells (see below, p. 75). This 
section, therefore, agrees completely with many of those on the south 
shore of the Main Island, described below. 
Excellent exposure of the bard Walsingham limestone occurs at 
many places, just above high water mark, on the south side of the 
Main Island, from west of Tucker’s Town to Elbow Bay, and 
perhaps further. 
The best examples that I saw are at the foot of a low bluff, near 
Hungry Bay, where the harder layers had been quarried by blasting. 
A good series of photographs of the rocks along this bluff, some of 
which are reproduced in my plates, were made in the spring of 1901, 
by A. H. Verrill. A violent hurricane, not long before, had washed 
away the debris and cut away the softer overlying rocks, so as to 
show all the strata very beautifullyt (see fig. 11). 
The hardest stratum (5) at this place is about one and a half to 
two feet thick, and has been blasted off for building purposes. It is 
a very compact, white limestone, almost like marble in some places, 
and often with no trace of sand-drift structure, though showing this 
at times in the continuation of the same section. It is overlaid in 
some places by a thicker and somewhat softer stratum (0’) of the 
same nature. 
The latter carries on its upper, nearly level, and somewhat eroded 
surface, portions of a firmly adherent layer of indurated red clay, 
commencing in which, at one place (plates xix, xx), there are large 
numbers of those cavities called molds of “ palmetto stumps,” men- 
tioned above, some of which penetrate into the hardest stratum of 
* See his description of the cavern, quoted below, p. 82. 
+ See pls. xvi-xx; also these Trans., xi, pls. lxxxiv-vi; and ‘‘The Bermuda 
Islands,” same plates. See discussion of their nature in chapter 24, Paleontology. 
