496 
Smyrna, where it contains Hippurites; he found the same lime- 
stone also in the Peninsula of Cape Krio, near Cnidus, at the 
south-west extremity of the Gulf of Cos ; and blue crystalline lime- 
. stone at Seala Nuova, and at Boodroom on the hills north of the 
town, under the remains of the Acropolis of Halicarnassus. The 
island and shores of the Gulf of Syme are also composed of a mass 
of compact white scaglia or chalk with bands and nodules of sili- 
ceous limestone. 
The greater part of the Island of Rhodes is composed of chalk 
containing flints, forming a prolongation from the chalk of Mount 
Taurus, and partially covered with tertiary strata. In Mount Atairo, 
the scaglia rises to a narrow ridge nearly 4000. feet high. The 
Acropolis of Camiro also stands on atable-rock of chalk. In Rhodes 
the chalk is partially covered with tertiary formations. 
Mr. W. C. Williamson has furnished a notice on some fossil shells 
from Syria, collected chiefly on a part of the Lebanon range im- 
mediately above Beyroot: the rocks are here composed of hard 
cream-coloured limestone containing many veins of flint; the shells, 
of which twelve species have been sent home, one of them a Hip- 
purite,; and a single fish, Clupea brevissima, Ag., tab. 61. f. 6, mndi- 
cate a near alliance to the chalk formation. We have similar 
evidence of chalk on Mount Lebanon in the well-kuown fishes from 
that range, which Agassiz refers to the epoch of the cretaceous 
deposits. 
IGNEOUS ROCKS. 
We have, from the Rev. D. Williams, an account ofa mass of trap, 
intersecting the mountain limestone, red marl and lias at the W. end 
of Bleadon Hill, on the Bristol and Exeter Railway. It resembles in 
its character that of Hestercombe, on the flank of the Quantoe 
Hills N.W. of Taunton, and is the first discovery of trap connected 
with the line of elevation of the Mendip chain. This protrusion of 
trap is attended by a remarkable fault, which brings the edges of 
bent strata of lias into contact with those of mountain limestone. 
Mr. Penistone has also supplied an instructive section of this cut- 
ting. The nearest known trap rocks to the Mendips are that of 
Hesereonibe in the Quantoe Hills just mentioned, and that near 
Tortworth and Berkeley. 
In a paper on the Isle of Madeira, Mr. Smith of Jordan Hill has 
supplied, I believe, the first geological description of this island, the 
structure of which has long been a desideratum to geologists. Little 
has hitherto been known. beyond the fact that all its shores and its 
general aspect are volcanic; Mr. Smith has at length discovered 
sections at the elevation of about 2000 feet, in the central part of 
the island, which exhibit compact limestone, containing fossil re- 
mains of Conus and many other shells of the tertiary period. No- 
thing is visible beneath this limestone, but above it are lofty preci- 
pices which exhibit several beds of sub-aérial lava, lapilli and ashes, 
alternating with beds of soil converted to brick by the beds of lava 
incumbent on them. In some of these volcanic beds of loose tex- 
