Notices of Memoirs-—— Volcano of Mergellina. 205: 
grounds, are supported by the depth of the cireumpolar sea, so far 
as it is known. The submarine shelf of the Austral land slopes 
northward all round the shores of the known lands more gently 
than along any other coast, and would seem to indicate that, if 
elevated, the land would form in great extent a continuation of the 
three primal ridges of the globe southward, coalesced and spread 
out round the Pole, with, between these arms, the terminations of 
the great and permanent ocean troughs. How far these hypotheses 
may be substantiated or refuted by future researches it is difficult 
to say; but the discovery of Aphanapteryx bones on the Chatham 
Islands must always remain an important fact in the solution of this 
most difficult and intricate question.” 
IJ.—Tur Supposed QuATERNARY AND SINCK SUBMERGED VOLCANO: 
or Mereutuina, at Napuss.’ By Chev. W. P. Jervis, F.G.S., ete. 
()* entering the Bay of Naples by steamer the first thing which 
must have struck every geologist—leaving aside Vesuvius for 
the present—is the line of flat-topped hills stretching along the 
northern shores of the Bay, from Cape Posillipo to- the Chiatamone, 
above the Castel dell’Uovo, their summits in no place exceeding 
from 160 to 200 metres in height, except at the Castel Saint’ Elmo 
(224m.) while they extend inland from the Vomero to the culmi- 
nating point at the old Camaldoli convent, above Pianura (455m.). 
These hills are essentially constituted of irregular strata of ochreous- 
yellow volcanic tufa of various tints, passing on the one side to pale 
yellowish white, and on the other to yellowish brown. This tufa 
is accompanied by frequent alternating beds of extremely fine 
volcanic ashes, and others often exclusively formed of impure-white 
or ash-grey pumice in angular pieces, ranging from less than a 
quarter-of-an-inch to several inches across, and adhering slightly 
together, though easily separated by the hand. Fragmentary pumice 
also exists in a certain proportion as a constituent of the volcanic 
tufa itself, in such case partaking in general of the coloration of the 
rock in which it is imbedded, being of a yellowish brown, and only 
in some places white, for instance near Piedigrotta. Sometimes the 
pumice is dark yellowish-brown, this variety, as well as the paler 
kind, being much decomposed, or what might be called in ordinary 
language rotten, so as to crumble when an attempt is made to 
detach it from the enclosing rock, for it is only when the pumice 
retains its original whitish or ash-grey appearance that it preserves. 
any consistency or is of any economic value. 
It will be immediately observed, on the most superficial examin- 
ation, how remarkably irregular is the bedding of even the thickest. 
strata, as they rapidly thin out, and often disappear altogether, to 
be replaced by others of very different lithological structure. As 
if to add to such irregularity, the dip of the beds is very varying 
and inconstant ; in one spot it appears to be horizontal, a few yards 
beyond it is not unfrequently undulating, and further on inclined 
1 From the ‘‘ Mediterranean Naturalist,’’ October 1, 1892. 
