Correspondence — Prof. E. Hull. 45 



measures from that formerly suggested by Prof. Phillips. He 

 pointed out that marine and freshwater species of fish appeared to 

 co-exist in the Carboniferous beds, and compared this with the 

 analogous case of the Lake of Nicaragua, as described by the late 

 Mr. Belt. Freshwater forms of sharks are not unknown in the 

 Ganges and other rivers. 



3. " On the Distribution of Boulders by other Agencies than that 

 of Icebergs." By C. E. Austin, Esq. ,C.E., F.G.S. (a theoretical paper). 



COBEESPOITDBITGE. 



ADDITIONAL NOTES ON THE NOETH DEVON SECTION. 



Sik, — Permit me to make one or two additional notes to those 

 contained in the Geological Magazine for December on the North 

 Devon Section. 1 Since they were written, the volume of Proceedings 

 of the British Association for 1877 has come to hand, containing 

 a short paper by Prof. G. Dewalque, " On the Devonian System in 

 England and in Belgium," 2 which is of much interest at the present 

 time, as corning from so high an authority on the Devonian question 

 as regards Belgium and its borders. M. Dewalque comes to the 

 conclusion (1) that the North Devon series is perfectly continuous from 

 Barnstaple to Linton; and (2) that " nowhere is there a reappearance 

 of such identical rocks as to prove, by repetition of the series, the exist- 

 ence of a fault," so that Mr. Etheridge's views and those of observers 

 who agree with him receive an important confirmation on this point. 



M. Dewalque also concurs in the view that the Pilton and 

 Barnstaple Beds are of Lower Carboniferous age, in fact repre- 

 sentatives of the Carboniferous Limestone, in which case the 

 underlying " Baggy and Marwood slates," with CucuUcm, must 

 be the representatives of the Lower Carboniferous slate and Coom- 

 hola Grit of the South of Ireland. I have just discovered that 

 this view was for the first time advocated by the Bev. Professor 

 Haughton, F.B.S., in a valuable paper on " The Evidence afforded 

 by Fossil Plants as to the Boundary-Line between the Devonian 

 and Carboniferous Bocks," published in 1856. 3 The concurrence, 

 therefore, of evidence and opinion on the age of these beds may, 

 I think, be considered to have completely established the Carbon- 

 iferous age of those beds hitherto generally considered as " Upper 

 Devonian." 4 



On the other hand, the opinion of Professor Dewalque on the 

 marine origin of the " Cornstone Group " of Hereford, will afford 

 surprise in some quarters. 



In conclusion, allow me to make a correction of a clerical error 

 in my paper. For "it," p. 531, line 11 from top, read ; ' this 

 division." Edwakd Hull. 



Dublin, Bee. 14, 1878. 



1 " Possible Explanation of the North Devon Section," by Prof. E. Hull, Geol. 

 Mag. December, 1878, p. 529. 



2 Brit. Assoc. Pep. 1 877, Trans, of Sections, p. 69. 



3 Journ. Geol. Soc. Dublin, vol. vi. p. 227- 



4 " Siluria," 4th edit. p. 272. H. B. Woodward, " Geology of England and 

 Wales," p. 69. 



