500 PROF. H. A. NICHOLSON AND MR. J. E. MARR ON 



27. The Cross Fell Inlier. By Prof. H. A. Nicholson, M.D., 

 D.Sc, F.G.S., and J. E. Marr, Esq., M.A., Sec. G.S. (Read 

 Aprils, 1891.) 



[Plate XVII.] 



Contents. 



Page 



§ I. Introductory 500 



II. General Description of the Inlier 501 



III. Detailed Description of the Strata 501 



(rt) The eastern portion of the Inlier. 

 lb) The western portion of the Inlier. 

 IV. Ages of the different members of the Coniston 



Limestone series 509 



V. Conclusion 512 



Appendix I, By Alfred Harker, Esq 512 



Appendix II. By A. H. Foord, Esq 526 



§ I. Introductory. 



Since the " Description of an Insulated Group of Rocks of Slate 

 and Greenstone in Cumberland and Westmoreland, on the East 

 side of Appleby," given by Dr. Buckland in the Transactions of the 

 Geological Society (ser. 1, vol. iv. (1817) p. 105), a considerable 

 number of papers have been devoted to the Lower Palaeozoic rocks 

 of that region, but as references to these are given in Mr. Whitaker's 

 list of papers bearing upon the geology of the Lake District, 

 published in the late Mr. Clifton Ward's memoir oa " The Geology 

 of the Northern Part of the English Lake District," it is needless 

 to insert here an account of the bibliography of the area. An 

 excellent summary of the work which has been achieved is given 

 by Mr, J. G. Goodchild in a paper published in the Proceedings of the 

 Geologists' Association for 1889*. In this paper also considerable 

 additions are made to our knowledge of the rocks of the Inlier, and 

 to these we shall have occasion to refer. 



In the present paper, we have attempted to fix the ages of the 

 various formations of Lower Paleeozoic rocks in the Cross Pell 

 district, to determine their organic contents, and to compare them 

 with the corresponding rocks of other areas, rather than to give a 

 detailed description of the general structure of the region. This 

 latter will no doubt be done by the officers of the Geological Survey 

 who have been engaged in mapping the district, with far fuller 

 evidence than is at the disposal of those who have not examined 

 the region in an exhaustive manner. Nevertheless, as a general 

 knowledge of the structure of the region is necessary to understand 

 the details which follow, we liave drawn up a rough map which 

 will serve as a guide until such time as the official Survey map is 

 published, and we append a description which may serve to render 

 the principal features intelligible. 



* Proc. Geol. Assoc, vol. xi. p. 258. 



