144 Geological Society. 



2. ' The Carboniferous Limestone South of the Craven Fault 

 (Grassington-Hellifield District).' By Albert Wilmore, B.Sc, 

 F.G.S. 



As to the lithology of the beds, some are massive coarsely- 

 stratified limestones, made up largely of crinoids, or corals, or 

 shells (or mixtures of these) ; others are well-bedded, almost flaggy, 

 black limestones made up of finely comminuted matter, with 

 abundant foraminifera. There is every gradation between these 

 extreme types. Variation in lithological character is lateral as 

 well as vertical. 



The strata are much disturbed everywhere. A series of folds 

 strike roughly north-east and south-west, and are somewhat 

 complex. There is considerable repetition of beds, and thickness 

 is not so great as at first appears. This bears on the interesting 

 question of the comparison of beds north and south of the Craven 

 Fault. 



The well-known knolls ('reef-knolls') are discussed. Their 

 beds and those in the immediate neighbourhood are much disturbed. 

 Irregular coarse bedding, folding, and normal long-continued 

 weathering will explain most of their structural and other pecu- 

 liarities. A typical knoll is dissected (Swinden); and it is seen 

 to consist of folded, faulted, grey, coarsely-bedded limestone, with 

 numerous great joints and much evidence of internal ' weathering.' 

 Comparison of these knolls is drawn with the corresponding hills 

 in the dark well-bedded limestones. 



It is not easy to work out the exact zonal sequence, because of 

 the disturbed character of the strata and the prevalence of glacial 

 and fluvio-glacial drifts. The strata are apparently all Yisean (and 

 the Author does not think that there is anything lower than Middle 

 or Upper S). 



In some beds, and under some circumstances, fossils are exceed- 

 ingly plentiful and easily procured. 



Some corals receive more especial notice, such as Caninia 

 gigantea, Mich., which is distinctive of certain beds. Other species 

 of Caninia are found. New or not well-known species of Zaphrentis 

 are described. The Author briefly discusses the relationships of 

 the genera Caninia, Camjoojohyllum, Calophyllum, Zaphrentis, and 

 Amplexus. New(?) species of Lophophyllum are also described, 

 and the generic characters of Lophophyllum are discussed. There is 

 a remarkably localized distribution of some corals, and Syringopora 

 is very common in certain of the beds. 



Suggestions are made as to the advisability of the disuse of some 

 of the specific names. It is suggested that not more than four 

 species of Carboniferous Syringopora need be retained. 



