BRITISH DEVONIAN BRACHIOPODA. 3 



received from Dr. Kayser, of Berlin,^ Prof. F. Roemer, Herr Zugmayer, Prof. Zittel, 

 Professors L. de Koiiinck and Dewalqiie, F. Saiidberger, and others. Helped in so 

 able and zealous a manner I could not fail to fill up the pages and plates of this Supple- 

 ment with ranch new and instructive information. 



The geology of the Devonian Systems in Great Britain has been the subject of many 

 able investigations ; and the Devonian question, as it has been sometimes termed, has 

 given rise to considerable divergence of opinion, as observed by Mr. Townshend Hall in 

 his able article, " A Sketch of the Geology of Devonshire," in White's ' History, Gazet- 

 teer, and Directory of the County,' p. 60, 1878: — "The late Mr. Jukes, Director of 

 the Irish Branch of the Geological Survey," with an "intimate knowledge of the 

 Carboniferous strata of the West of Ireland entered into an argu- 

 ment to prove that the Devonian rocks do not form an independent system of them- 

 selves, but are in truth equivalents of the Carboniferous strata of Ireland. These views 

 have been vigorously opposed, chiefly on palseontological evidence, by Mr. Etheridge, 

 in a very elaborate paper on the " Physical Structure of the West Somerset and North 

 Devon,"' also by Mr. Townshend M. Hall, Mr. Champernowne, and others. 



Mr. T. Hall observing that the Devonian beds may be divided into two principal 

 areas, those of North and those of South Devon, classifies them as Loiver, Middle, 

 and Upper. 



Mr. Hall proposes to divide the North-Devon series into the following sequence of 

 beds in ascending order : 



^ XA . C Foreland Sandstone. 



Lower Devonian i , . , ,^ , 

 C Lmton Beds, 



/■Martinhoe and Hangman Beds. 

 Middle Devonian \ Ilfracombe Shales and Limestones. 



V. Morthoe Shales. 



/■Pickwell Down Sandstone. 

 Upper Devonian ■] Cuculsea or Marwood Zone. 



(• Pilton Beds.^ 



^ ' Quarterly Journal Geol. Soc.,' vol. xxiii, p. 5G8. 



2 See also a valuable paper by Mr. T. Hall in the ' Proceedings of the Geol. Soc' for June, 1867, " On 

 the Relative Distribution of Fossils throughout the North-Devon Series ;" refer likewise to a paper by Mr. A. 

 Champernowne, " On the Divisions of the Old Red Sandstone of North and South Devon," • Geol. Mag.,' 

 vol. V, May, 1878. We are informed by Mr. Pengelly that Pilton is now a suburb of Barnstaple ; Marwood 

 and Sloly are about three miles north by west, and two and a half miles north by east, respectively, from 

 that town. Baggy Point is the northern horn of Barnstaple and Croyde Bays, the latter being a branch 

 of the former. 



Brushwood is a village about one mile and a half south of Dulverton, and three and a half north-west 

 of Bampton. 



South Petherwyn is a village about two miles south-westerly from Lauuceston ; in Cornwall, the 

 fossils are chiefly found in the quarries of Landlake, in the parish of South Petherwyn. 



