* 
5p Bi. Deubenij en ihe Geolosy of Sicily. 
common, as it would appear, both to the chalk and the first 
tertias, jimesione,* nummulites and melanites are also fre- 
quent. 
It is, however, to the country intervening between Sortino 
and Lentini, that I would refer for the most satisfactory proofs 
of the real age of this formation, as we there see beds 
abounding in shells, which, if not confined to the most recent 
class of rocks, seem, nevertheless, in this instance, by their 
concurrence as well as frequency, to indicate the recent date 
of the beds which contain them. Among these, the cerithium, 
turritella, venus, and venericardia may be mentioned as fre- 
quent; and near Lentini, dentalia, strombi, pectines, casts’ of 
trochi, and nerite, also occur. 
I may add, that fossil fish have been found near Syracuse, as 
in the rocks of a similar epoch at Monte Bolca near Vicenza. 
With regard to the volcanic rocks with which these beds 
are associated, I may observe, that, whilst the cellular and 
semivitreous aspect of many of them is such as to preclude 
any class of geologists from entertaining doubts with respect 
to the manner of their formation; the characters of other 
portions present strong analogies to rocks of the trap family, 
which, whatever may be their origin, must have a much older 
date assigned to them. 
In some of the beds, for instance, there is a uniform com- 
pactness, and a lithoide fracture, which seems to indicate the 
presence of a certain degree of pressure; in others we may 
observe the presence of olivine, either disseminate in minute 
crystals through the mass, as in basalt, or assembled in 
nésfs. 
The cavities are also frequently filled up with calcareous 
spar or with zeolites, just like the amygdaloids of more an- 
cient strata ; and in some of the beds a tendency to a colume 
war arrangement is discernible. 
* According to Dr. Boué’s arrangement of Fossil Organic Remains, 
published in the number of the Edinburgh Philosophical Journal for Jan- 
uary and April 1825, it appears that the Hippurttis rotula and H. elong 
atus of Schlottheim belong to the chalk; the H. areolatus, H. turbino- 
tatus var. @, and H. renovatus, to the first tertiary or salt-water limes 
stone. 
+ At Palagonia, west of Lentini, the volcanic rock has a superficial 
Covering of obsidian, while it has internally a lithoide basaltic aspect, 
reminding one of the vein in the island of Lamlash, close to Arran, the 
sid@s of which are of pitclistone, whilst the centre is basalt. 
