104 MR. R. L. SHERLOCK ON THE RELATIONSHIP OF THE [Feb. IQH, 



[Cumberland & Westmorland succession .] Maximum thickness 

 B 2 . Magnesian Limestone Series. in feet. 



2 H . Magnesian Limestone. Impure cellular dolomite ... to 10 

 2 ! . Plant Beds (Marl Slate). Alternations of dolomitic 

 sandstones with thin bands of impure dolomite, clays 

 and shales, bands of lignite, and occasional thin coals. 

 Remains of Nceggerathia, JValchia, Ullmannia, and 

 bracts of cones. In the Helton Section these beds 

 may be 150 



B r Lower New Red or Roth-todt-liegende. 



l iv . Copper-red sandstones, usually devoid of mica and 

 generally containing much secondary quartz. Exhibit 

 footprints. 

 l iH . Upper Brockram; breccias of angular fragments of 



Carboniferous rocks. 

 1". Penrith Sandstone as l iv , but much rnore false-bedded, 



and usually coarser (unfossiliferous). 

 I s . Lower Brockram, as l iv [?]"']. The maximum 

 thickness near Appleby may be 1500 feet, but its 

 extreme variability and excessive false-bedding 

 render any exact estimate almost impossible ? 1500 



On the north-east side of St. Bees Head there is a well-known 

 section, showing Magnesian Limestone (2 U in the foregoing table) 

 with casts of fossils, resting on 3 feet of breccia, which overlies un- 

 conformably Carboniferous sandstones. Above the limestone there 

 is some 30 feet of red marl, succeeded by a 15-foot bed of gypsum, 

 which was mined until recently. A second bed of gypsum succeeds 

 this, separated by 2 or 3 feet of marl ; and, still higher, there is 

 an alternation of red marl and fine-grained sandstone-bands with 

 flakes of mica. These strata are very like the passage-beds between 

 the Permian Marl and the Bunter seen in Nottinghamshire, and 

 like them they pass up into sandstone, in this case the St. Bees 

 Sandstone. 



Sedgwick, 1 who first described this section, considered the 

 St. Bees Sandstone to be of Bunter age, and, seeing no break in the 

 succession, named everything above the Magnesian Limestone, Trias. 

 Later, in 1864, Murchison & Harkness, recognizing the gypsiferous 

 marls above the limestone as the equivalent of Murchison's Upper 

 Permian (Bunterschiefer), were for the same reason obliged to assign 

 the whole of the St. Bees Sandstone to the Permian : for it was con- 

 sidered, at that time, that there must be an unconformity between 

 the Permian and the Trias. 



Mr. T. V. Holmes (1881) agreed with Murchison in referring the 

 whole mass to the Permian ; whereas Goodchild followed Sedgwick, 

 and made everything above the limestone Trias. Dr. Irving 2 also 

 holds that the St. Bees Sandstone is of Bunter age. 



Mr. Holmes regards the Kirklinton Sandstone as Lower Keuper 



1 A. Sedgwick, 1836, p. 398. 



2 A. Irving, 1882, p. 163. 



