Dr, Paubeny on ihe Geology of Sicily. 245 
breccia, which at the time I was disposed to identify with the 
breccia seen everywhere associated with the preceding rock. 
At present, among the various omissions of which I accuse 
myself, but which the scantiness of accommodation, as well 
as the distraction of various objects, sometimes rendered un- 
avoidable, there is none I regret more than my not having 
fully made out the relations of the blue clay formation to the 
limestone which succeeds it between Terranuova and Cape 
Passero. 
I am, upon the whole, inclined to view it as resting upon 
the latter ; but, on looking back to my notes, | must confess 
that" do not find myselt authorized to state this, on any cer- 
tain grounds. 
I may however, express with more confidence, my _ belief, 
that the blue clay formation is of very recent date, belonging 
probably, to the Tertiary Epoch; and is not, as might be 
supposed, from the presence of salt and gypsum, related to 
the new Red or Muriatiferous Sandstone of the north of Ku- 
rope. 
There is nothing in the nature of its imbedded minerals to 
contradict such an opinion; for gypsum and selenite, sul- 
phur and sulphate of Strontian, are quite as characteristic of 
the Paris beds as of the secondary sandstone ; and common 
salt is said, by Steffens, to accompany the same rocks at the 
Segeberg in Holstein; and, by Humboldt, in New Anda- 
lusia.* 
My reasons for assigning to it this date are, its containing 
beds of blue limestone with shells, some of which (as Turri- 
telle) seem to bespeak a tertiary origin; its being accompa- 
nied, throughout its whole extent, by the recent breccia above 
noticed; and the probability that the amber of Sicily has 
been derived from this stratum,—a circumstance directly 
affirmed by Ferrara,} and favoured by the situations in which 
this mineral is chiefly met with; namely, at the mouths of 
rivers which have flowed through this rock. 
* See Humboldt’s Personal Narrative, Vol. I. p. 262, English Trans- 
lation, and Steffen’s Geogn. Aufsatze, p. 142. The description of the mu-. 
riatiferous clay of New Andalusia corresponds exactly with what we 
know of the blue clay of Sicily. , 
+ Vide Ferrara Campi Flegrei, p. 29. 
