TRANSACTIONS OF SECTION C. 809 
C. Zone of Bel. jaculum, Phil.—-In contrast with the preceding, this zone is 
feebly developed in the Acre House section, as compared with its great thickness 
and variety of fauna at Speeton. The Tealby clay falls wholly within the zone, but 
may represent only the upper portion of the Yorkshire section. It is possible 
that the top of the ironstone may in some place reach up into this division, but 
further research is needed. 
B. Zone of Bel. (semicanaliculatus ?)—The Upper, or Tealby, limestone in the 
neighbourhood of Normanby and Tealby contains many of the characteristic fossils 
of the lower part of the zone of Bel. (semicanaliculatus ?), but it is not yet possible 
to say to what height in the Speeton section this correlation should be extended. 
Consequently nothing definite can be stated with regard to the beds overlying 
the limestone, in which fossils are all but absent, but it is believed that the Car- 
stone may have its partial equivalent in the marls (A) at the base of the Red 
Chalk at Speeton. 
The paper concludes with some paleontological notes on the Speeton beds, based 
_ chiefly on a re-examination of the old collections ; and with arguments derived from 
_ these notes as to the age and relations of the series. 
By Professor H. G. Sretzy, F.R.S. 
The author described the vertebra of Ichthyosaurs and showed, on the evidence 
of specimens in the British Museum and that of A. N. Leeds, Hsq., that the 
neural arch has no zygapophyses or zygapophysial facets, but that there is a single 
flat median facet of vertically ovate form above the neural canal back and front, 
which is termed a proto-zygapophysis. The character has been found in many 
Species from the Lias and lower Oolites, and in Ophthalmosaurus from the Oxford 
clay. 
8. On the Neural Arch of the Vertebree in the Ichthyosauria. 
d 
9. On the Marbles and other Ornamental Rocks of the Mediterranean. 
By W. Brinvinry, 7.G.8., F.R.M.S. 
White marbles only were used by the Classic Greeks, this material as a 
superior building stone being the most plentiful, and no doubt its purity had great 
influence on the refinement of their architecture, colour afterwards being applied 
to reduce its dazzling brightness. The Romans, following the Greeks, endeavoured 
to get lasting colour effect by the use of coloured marbles, every shade of which 
was found on the shore of the Mediterranean Sea. The Greek quarries of 
Pentelicus and Paros were very extensive, and are still workable. Under the 
Roman Empire there does not appear to have been any workable rock, even in 
the most remote spots. They did not find and transport to Rome. From 
Carystus in Eubcea were taken the Cipollino monoliths of the Temple of 
Antoninus and Faustina. The shores of Thessaly and Magnesia supplied the 
Various greens ; Synnada, the choice Pavonazzetto Antico, used in the Pantheon : 
these quarries, sixteen in number, have just been rediscovered, and are workable. 
Those of Giallo Antico in Tunis, the ancient quarries of Numidia, are now 
ensively worked. The quarries of Rosso Antico and Green Porphyry are in 
_ duaconia. 
___ Down the Nile was brought the Oriental alabaster, the granite monoliths of the 
_ portico of the Pantheon and Forum of Trajan. Also down this river came the 
_ Most sumptuous decorative stone the world has ever known, namely, Imperial Red 
Porphyry ; blocks, 20 tonsin weight, were procured, as seen in the Vatican. These 
quarries are now being reworked, and 280 small blocks from them haye just 
‘arrived in London, many of which show the old methods of working, namely, 
splitting with wedges, scappling into rough shapes with hammers, rough and smooth 
pickaxed dressing, and truthfully sawn faces 2 feet in Jength. The coast of 
' Published in full in the Builder, September 20, and the Building News, 
_ September 19, 1890. 
1890. 3@ 
