242 
NOTE ON THE ZONES OF THE CARBONIFEROUS LIMESTONE SOUTH 
OF THE CRAVEN FAULT. 
BY ALBERT ^^^:LMORE, D.SC, F.G.S. 
I wish in this brief note to give some indications of progress 
in the investigation of the zonal sequence in the area dealt \vith. 
in my previous papers. These papers have been chiefly concerned 
with the lithology, \viih a general statement of the chief fossils 
found in the different exposures, and v^ith the description of certain 
characteristic corals. For some time past I have been at work 
trying to work out the zonal sequence in this most complicated 
area, taking as my key, of course, the well-known Avonian sequence 
and also comparing with other localities. The work will evidently { 
be prolonged as the district is much disturbed. A number of 
misconceptions have also retarded one's progress. 
It has been assumed that all the Craven Lowland area is 
occupied by Dr. Vaughan's Dibunophyllum zone, but this is clearly 
a mistake. It is probable that we have representatives of all the 
zones do^^Ti to Z. 
All the knoll limestones are not on the same horizon. The 
knolls of Downham and Clitheroe are much lower than those of 
Cracoe for example. The latter are most certainly high D, but 
the former are probably upper S or ver}^ low D. The great knolls 
of Elbolton and Swinden seem to include both S and D beds. 
The small exposures of white limestone at Crag Laithe and at 
Fogger seem to be in upper S., whilst the small patch of white 
limestone at Winterbum Reservoir is probably in D.l. or S.2. 
Mistakes have also been made concerning the " Shales-with- 
Limestone " of the Survey. There has been a tendency to include 
them all in the Pendlesides. Those of Gill Rock near Barnolds- 
wick, for example, where the Survey officers drew a definite line 
between the limestone massif and the shales-with-limestone, are 
well down in the sequence, lower Visean or even Tournaisian. ' 
