44 VAUGHAN : THE KNOLL REGION OF CLITHEROE, ETC. 
SHALES-WITH-LIMESTONE. 
These beds are characterised throughout by Glyphioceras {Sphen- 
oceras) crenistria and Proleca?iites compressus and, especially in the 
upper portion, by Cyathaxonia rushiana and rare Zaphrentes . 
On Pendleside, they contain abundant Prolecanites at the base 
and frequent Cyathaxonia and Sphenoceras"^ in the Pendleside Limestone 
which caps the series at Phynis, close to the top of the limestone- 
massif of Slaidburn, a considerable collection was made by the members 
of the Yorkshire Geological Society during our recent visit, from 
the base of the Shales-with-Limestone. The result was to definitely 
fix the level as D 2-3 of Gower (S. W. Province), the facies being that of 
the Oystermouth " Black-Lias " Quarry, near Mumbles. Other 
localities (Croasdale etc.) near Slaidburn, confirmed this general 
conclusion, viz : — that the Shales-with-Limestone are upper D in age 
and under P. 
CLITHEROE KNOLLS. 
These were all included together by Mr. Tiddeman in the upper 
division of the Clitheroe Limestone ; there are, however, two distiijct 
lines of knolls at two distinct levels, viz. : — 
A lower line (Pimlico to Downham) of Waulsortian (Mid-Avonian) 
age included within the zone of Productus siiblcevis and itself contain- 
ing fossils of St. Doulagh (Dublin) facies and a higher line (Salt Hill, 
Warsaw, Twiston) of Visean age. The level attained is variable in 
the several knolls (for example, low S in Salt Hill) but in my opinion, 
never reaches D2. 
In Bowland, the Ashknott Knoll has yielded the most advanced 
Brachiopods, but, even here, forms common in D2 are infrequent. By 
kind permission of Mr. King Wilkinson, we collected from the large 
Dunnow Knoll, near Slaidburn ; and, to the generosity of Miss Peel 
of Knowlmere, I am indebted for an exhaustive collection from the 
Knowlmere Quarries. The Brachiopods from both these localities 
contain very few characteristically D forms and suggest for them a 
level somewhere in S, near that of the Upper line of Clitheroe knolls. 
* Sphenoceras is a sub -division of Glyphioceras, and includes 
Gonintites sphericus, G. crenistria, and Go siriatus. 
