38 WILMORE : THE STRUCTURE OF SOME CRAVEN LIMESTONES. 
from the fine amorphous rock mud in a manner somewhat 
analogous to the development of porphyritic crystals in igneous 
rocks after and during devitrification. 
Thirdly, there is a fine crush breccia, already mentioned 
in an earlier part of this paper. 
There are several exposures in the somewhat dome-shaped 
mass between Gargrave and Broughton. The most interesting 
is an old quarry near Pasture House, known as Clint's Delf. The 
strata dip N.E. and N.N.E. at varying angles from 30° to 60°. 
The sequence is as follows : — 
Very massive limestones, with partings of crinoidal mud 
and shale. 
Mud bands, full of fossils. 
Thick limestones. 
Shales. 
Dark earthy hmestones. 
Dark earthy shales (bottom beds). 
Exceedingly fine fossils may be obtained here. The follow- 
ing is a list of the commoner types : — 
Many species of echinodermata (stems, plates, spines) 
in most exquisite preservation. 
" Cups " of Platycrinus and Poteriocrinus. 
Archceocidaris sp. 
Syringopora genicidata. 
ramulosa. 
Zaphrentis sp. 
Fenestella and Polypora. 
OrtJiis Michelini and other brachiopods. 
Euomphalus sp., and other gasteropods. 
These beds are mapped as being at the summit of the Car- 
boniferous Limestone, and the country to N, and N.E. is mapped 
as Yoredale " shales with limestones." There is, however, an ex- 
posure about three-quarters of a mile to N. of Clint's Delf where 
characteristic limestone fossils occur in a grey, somewhat flaggy 
limestone. 
It is noteworthy that the whole of the district possesses 
the characteristic limestone geography. There are not many 
exposures, two or three old grown-over quarries being the only 
