261 
Dr Baubeny on the Geology of Sicily. 
In the country between Terranuova and Cape Passero, the 
only shells I observed were near the little town of Scicli, where 
they consisted chiefly of pectens and ostrese. I have also, from 
this locality, the cast of a shell which resembles an area. 
At Cape Passero, however, the fundamental rock is not of 
Neptunian, but of Volcanic origin. At the level of the sea, and 
rising to a considerable height on the cliff above, is a tuff, the 
basis of which is a species of dark indurated clay allied to wacke, 
and the imbedded portions are composed partly of compact and 
partly of cellular lava. 
This tuff, as the aggregate may be called, is often amygda- 
loidal, little spherical concretions of calcareous spar, being dis- 
seminated through it, and in these cases I have observed, inter- 
mixed with the wacke, numerous crystals of a mineral of the 
hornblende family, which I believe to be schiller spar. In other 
cases the calcareous matter has penetrated uniformly into the 
interstices of the rock, and cemented together its parts. 
This volcanic tuff is covered towards the summit of the cliff 
by a bed of limestone, which extends to a little island opposite, 
on which the Castle of Cape Passero is erected. The limestone 
is very different in its external characters from that which I had 
followed from Terranuova. It is of a more crystalline and 
compact structure, bearing a much nearer resemblance to the 
limestones of the older strata, than the preceding beds * *. 
Its usual colour is white, but it is sometimes veined with blue, 
forming, in appearance at least, a kind of breccia. 
The shells it contains are numerous, nummulites are abun- 
dant, as are also madreporites and melanites. But the most re- 
markable petrifaction is the hippurite, first discovered I believe 
Pantalica, and in the valley of Ipsica, the rock is completely honeycombed with 
them ; and it is difficult to tell, whether they were designed for sepulchres or ha- 
bitations, at all events, they belong to a people anterior to the period of Greek 
colonisation. The general size of the excavations was about six feet square ; and 
at Pantalica, they were so regularly disposed along the abrupt face of the rock, 
that they resembled the ranges of windows, belonging to the several storeys of a 
long building. They seem to be confined to the south of the island, where the 
stone is soft, and easily hollowed out. 
* My friend Mr Delabeche, who is just returned from Jamaica, shewed me 
some specimens of tertiary rocks from that island, which, in point of compactness, 
quite equal those of Cape Passero. 
