Proceedings of the British Association. 365 
mens ; but it would be impossible, without plates, to convey to the 
reader any accurate notion of these highly interesting organic re- 
mains. They belong to two new genera established by Dr. Riley 
and Mr. Statchbury, | the Palzosaurus and Thecodontosaurus ; and 
were found in the magnesian conglomerate which at Durdham Down 
reposes on the carboniferous limestone. They must have been de- 
posited upon the spot where they were found without violent action, 
as they bear no marks of attrition. Perhaps the most interesting 
fact mentioned, was the peculiar structure of the vertebra of the 
newly discovered saurians, which presented a remarkable contrast to 
those of the recent crocodiles. He shewed a singular gradation from 
the recent saurians to sauroid fishes, by means of this arrangement 
of vertebre, which thus becomes an excellent guide in the discrimi- 
nation of the saurian animals; and he concluded his communica- 
tion with a quotation from Agassiz, respecting the progressive de- 
velopment of animal life.-—Dr. Riley alluded to the extraordinary 
structure of the cerebral column of these extinct saurians, as likely 
to illustrate the supposition of Dr. Gall, that the spinal column of 
vertebrate would be eventually found to correspond with the gan- 
glionic system of invertebrate animals.—Dr. Buckland was particu- 
larly struck with the singular structure of these vertebra, as indica- 
ting in the animal a nervous power of the most extraordinary char- 
acter. 
A paper was read by Mr. Hopkins, containing theoretical views 
respecting the geological phenomena of elevation. The principal 
object of the author in this paper, was to investigate the effects of 
an elevating force acting simultaneously at every point, on portions 
of the crust of the globe of considerable superficial extent ; and to 
shew that the theoretical inferences deduced from this hypothesis, 
are in striking accordance with the phenomena he had observed in 
the limestone and coal districts of Derbyshire. He also proved that 
in that district the direct cases of dislocation were not such as coul 
result from the influence of the jointed structure as the determining 
cause of those directions. He pointed out how the theory he had 
discussed will account for nearly all the phenomena of mineral veins, 
which can be attributed to mechanical causes ; as well as for the for- 
mation of systems of anticlinal lines, of faults, and of the phenomena 
of elevation.—Mr. Sedgwick considered this as the most important 
communication as yet ‘made to the Section. We should now be 
wale to indulge in the same speculations in Geology, as in her 
