SCIENTIFIC SUMMARY. 
201 
called Peperino, so much employed in buildings at Naples, in which zones 
or lenticular blotches of different mineral character alternate throughout the 
rock, the augitic matter having apparently separated itself from the more 
feldspathic by a. process of segregation during the efflux of the lava. And 
Mr. Scrope thinks there need be little doubt that what has taken place in 
this instance on a small scale has frequently occurred on the large one, 
within the focus of a volcano, during the, perhaps repeated, processes of 
alternate fusion and re-crystallisation, to which a mass of subterranean lava 
has been probably exposed, under varying circumstances of temperature and 
pressure. 
Hungarian Fossil Corals . — At the meeting of the Royal Academy of Vienna 
on the 13th of January Dr. Reuss presented a memoir entitled “ Upper Oli- 
gocene ( Oberoligocdne ) Corals of Hungary.” It contains the description of 
corals from beds, hitherto held to be eocene, of the tertiary formations of 
Mogyoros, Tokod, Dorog, Bayoth, in the vicinity of Gran, in Hungary. 
A new Wealden Vertebra. — Mr. J. W. Hulke, E.R.S., whose labours as a 
geologist are almost unceasing, read a paper on this subject at the meeting 
of the Geological Society on the 9th of February. The specimen described 
was one which he obtained last autumn at Brook, Isle of Wight, remark- 
able for its great size, its extremely light structure, and the extraordinary 
development of the processes connected with the neural arch. It consists of 
a thin outer shell, inclosing a very open cancellated tissue, having extremely 
large spaces, comparable with those of Pterosauria, and surpassing those of 
the cancellous tissue in any of the known larger Dinosaurs. A wedge and 
notch, similar in principle to the ophidian zygosphene and zygantrum, but 
differently placed, are superadded to the ordinary articular processes. A 
broad horizontal platform stretches along the side of the arch from the 
transverse process to the postzygapophysis. The neural spine is composite ; 
all the outstanding parts are supported and strengthened by thin bony plates. 
Only a small part of the centrum is preserved, so that the form of this, and 
in particular of its articular faces, is not determinable. In concluding his 
account Mr. Hulke noticed certain textural resemblances between the ver- 
tebra and a peculiar Streptospondylian vertebra in the British Museum, from 
the Weald of the south-east of England. 
Railway Sections at Sevenoaks . — Railway sections afford such an easy and 
excellent mode of studying geology, that the paper read by Mr. Caleb Wil- 
liams, F.G.S., before the Geologists’ Association (March 4) deserves atten- 
tion. The paper is of too great a length for abstract, but is published in full 
in Scientific Opinion. The author described in detail the various deposits 
passed through in constructing the tunnel (3,451 yards in length), and on 
the range of hills on which Sevenoaks is situated, and the sections seen in 
the cuttings to the north of that tunnel. The lowest beds traversed by 
these works are of fresh-water origin, are only seen in the neighbourhood of 
Sevenoaks Weald, and consist of grey, blue, and greenish clays, with many 
layers of flattened bivalve shells or the genera TJnio and Cyrma. Many of 
the layers are studded with great numbers of Cyprides, mostly as casts ir the 
clay. Detached fishscales are dispersed throughout this group of beds, the 
rhomboidal scales of Lepidotus being the most abundant. 
Birds of the Middle Tertiary of France . — In a paper presented to the 
