360 
pears, and the convolutions consist of imterblended layers of cement 
and dentine. ‘Thus, on the supposition that the tooth of the Laby- 
rinthodon of the German Keuper be capped with enamel, its extent 
must be less than in the tooth of the Warwick sandstone. 
The inflected folds are continued for a greater relative distance 
before the lateral inflections commence than in the German species, 
and the anfractuosities are fewer in number, and some of the folds 
are reflected backwards from near the central pulp-cavity for a short 
distance before they terminate. 
The modifications of the complex diverging plates of the dentine 
hardly exceed those of a specific character, and the dentine itself is 
composed of calcigerous tubes of the same relative size and dispo- 
sition as in the Labyrinthodon Jaeger. 
In a section taken from the middle of a smaller and relatively 
broader ‘and shorter conical tooth from the Warwick sandstone, Mr. 
Owen found that the anfractuosities were more complicated, with 
numerous secondary and tertiary foldings, and the external layer 
of cement was relatively thicker than in the Lab. Jaegeri. 
The generic identity of the Reptiles, indicated by the teeth from 
the Warwick sandstones, with the Mastodonsaurus of the German 
Keuper, Mr. Owen believes to be fully established) by the concord- 
ance of their peculiar dental structure above described. And in con- 
clusion, he says, if, on the one hand, geology has in this instance 
really derived any essential aid from minute anatomy, on the other 
hand, in no instance has the comparative anatomist been more in- 
debted to geology than for the fossils which have revealed the most 
singular and complicated modification of dental structure hitherto 
known ; and of which not the slightest conception could have been 
gained from an investigation, however close and extensive, of the 
teeth of existing animals, 
A paper was next read, entitled ‘‘ Observations relative to the 
Elevation of Land on the shores of Waterford Haven during the Hu- 
man Period, and on the Geological Structure of the District ;” by 
Thomas Austin, Esq. 
‘The shore on the west side of Waterford Haven, from the rock of 
Passage to Woodstown, a distance of three miles, presents an almost 
uninterrupted cliff of clay and gravel, composed chiefly, if not wholly, 
of detritus of old red sandstone, and enclosing a bed from one to 
four feet thick of Cardium edule, with other marine testacea of exist- 
ing species, and a few land-shells. ‘his bed of! shells:is not con- 
fined exclusively to the coast, but it extends inwards to the distance 
of eight miles, distinct traces of it occurring between Waterford and 
Tramore, and at several intermediate points. Inthe alluvial valley 
of Woodstown, close to Newtown Head, the shells: rest onan ancient 
peat bed, raised but a few inches above the sea-level. On the eastern 
side of Waterford Haven beds of similar shells occur at the same 
level; also in the cliff north of Bluff Head, at the height of eight 
feet.. The greatest elevation at which the shelly beds have been ob- 
served by Mr. Austin in the county of Waterford, is. forty feet. 
