Geological Society of London. 107 
The remains of at least two distinct Saurian animals have been 
discovered by Dr. Riley and Mr. Samuel Stutchbury, in the dolo- 
mitic conglomerate of Durdham Down near Bristol. They are al- 
lied to the Icuana and Monitor, but the teeth, vertebra, and other 
bones exhibit characters by which they are seen to be generically 
distinct from all existing reptiles. ‘They are particularly deserving 
of your attention as occurring in the bottom of the magnesian lime- 
stone formation, the oldest strata in which the bones of reptiles have 
as yet been found in Great Britain. ‘The most ancient examples of 
fossil reptiles known on the continent of Europe, occur also in the 
zechstein of Germany, a formation of about the same age. 
I alluded last year to a memoir of Sir Philip Egerton’s, in which 
he pointed out some peculiarities in the structure of the cervical 
vertebre of the Ichthyosaurus. He has now proved that in all the 
species of this genus there are three accessory bones, which he pro- 
poses to call, from their shape and position, subvertebral wedge 
bones. They are supplementary to the atlas, axis, and third ver- 
tebra of the neck, and seem to have escaped the observation of Cu- 
vier and other osteologists. 
Mr. Lewis Hunton has communicated to the Society an elaborate 
account of a section of the upper lias and marlstone in Yorkshire, 
showing that different beds in those formations are characterized by 
particular species of Ammonites arid other Testacea, each species 
having a limited vertical range. His observations are valuable not 
only as illustrating the distribution of fossils on the coast near Whitby, 
but also as furnishing a point of comparison between that district 
and many others in Great Britain. Mr. W. C. Williamson of Man- 
chester has had the same object in view in studying the fossils of 
the oolitic formations of the coast of Yorkshire, and informs us, as 
the result of his patient investigation, that although certain assem- 
blages of fossils abound in particular subdivisions of the oolite, many 
_ species range from the lowermost to nearly the highest beds. ‘This 
inference is confirmed when we compare the lists drawn up by Mr. 
Williamson, and those published by Prof. Phillips and other com- 
petent authorities. Thus some of the shells of the inferior oolite, 
mentioned in Mr. Williamson’s list (Trigonia gibbosa, for example,) 
occur also in the Portland stone of Wiltshire; another, as Ostrea 
Marshii, is characteristic of the cornbrash in the same county ; 
others pass downwards to the lias, as Orbicula refleca and Ammon- 
ates striatulus. If you consult the tables of organic remains which 
