Dr Daubeny on the Geology of Sicily. 117 
merits of chert which cover the surface here as in many portions 
of the limestone district in Derbyshire ; whereas, the formation 
now about to be described, affords the finest crops of corn, and 
is distinguished, even where uncultivated, by the luxuriance of 
the plants that grow every where upon it. 
This formation consists either of a coarse puddingstone, con- 
taining rolled and angular fragments of quartz, and of the com- 
pact limestone on which it rests, or of a calcareous breccia, in 
which sand is also present, though limestone be the predomina- 
ting ingredient. 
Wherever the latter variety is found, shells are very abundant, 
so that we may be led to attribute the presence of calcareous 
matter in this instance, principally to the accumulation of de- 
cayed organic bodies. 
The genera of shells commonly most frequent in this rock, 
are the Pecten, Ostrea and Venus; but in that variety of it which 
occurs at the foot of Mount Pelegrino, and is only distinguished 
from the former by its greater freedom from sandy matter, and 
the consequent whiteness of the rock, Serpulse, Dentalia and Ve- 
nericardiae, may be distinguished along with those already men- 
tioned. 
I may remark once for all, that a breccia of this kind, replete 
with shells, not far, if at all, removed from existing species, seems 
to fill up the hollows in most of the older rocks of Sicily. Thus, 
a formation of this kind exists, as I am informed, at Messina, 
though, being at that time occupied on other subjects, I did not 
observe it. The same formation occurs at Syracuse, and along 
the coast upwards towards Catonia, where it must not be con- 
founded with the calcareous rock afterwards to be described, 
which alternates with volcanic tuff®. Between Taormina and 
Giarre at the foot of Etna, is a limestone with shells similar to 
the above, which alternates with a yellow sandstone ; these beds 
seem to repose upon the older lavas. 
The same recent formation occurs in various situations along 
* If a statement of Ferrara’s be correct, the breccia above mentioned must be 
formed by causes now in action, like the indurated sand of the coast of Cornwall ; 
for this author states, that remains of the utensils of mariners have been found in 
it. This, however, cannot be the case with respect to the breccia which covers the 
blue clay, for in this we have abundant evidence of diluvial action. 
