THEIR DISTRIBUTION. 
89 
presence of spatangus ovalis, and ammonites perarmatus, and the ab- 
sence of product®, axini, ammonites Walcottii, nerita costata, astarte 
minima, and terebratula digona. 
2. Again, the Kelloways rock differs from all the strata above it and 
below it, by the presence of ammonites calloviensis, and grypha?a 
dilatata: no stratum in Yorkshire but the Kimmeridge clay contains 
ostrea delto'idea ; nor is gryphasa incurva found except in lias beds or 
lias boulders. 
S. It is in the lower part of the coralline oolite that clypeus dimidi- 
atus, and c. clunicularis abound, but melania striata belongs to the upper 
layers of that rock. 
These are the principles of investigation which it is proposed to 
apply to the strata and fossils of the eastern part of Yorkshire, and to 
illustrate by the aid of the arranged catalogues which follow, and their 
accompanying plates. 
I shall first present complete lists for each stratum, of all the fossils 
found in it, distinguishing those which are repeated in other strata, and 
referring to figures contained in this work, Mr. Sowerby’s Mineral Con- 
chology, Mr. Smith’s Woi’ks, Mantell’s Geology of Sussex, Young and 
Bird’s Survey of the Yorkshire Coast, Kendall's Catalogue of Scar- 
borough Minerals and Fossils, Parkinson’s Organic Remains, &c. 
After thus unfolding the evidence which I have collected on the 
subject, I shall venture to propose some inferences concerning the dis- 
tribution of organic remains in the rocks of the country which I have 
undertaken to describe, and likewise endeavour to trace the extent of 
the agreement in this respect, between the strata of Yorkshire and those 
of Scotland, the southern counties of England, and some parts of the 
continent. 
Lastly, I propose to combine the whole into one synoptic list of the 
organic remains mentioned in this work, arranged in the ascending order 
N 
