Upfield Green — The Cornish Beds and the Gedinnian. 405 



Notes (Dublin, 1867) ; Etheridge, Quart. Journ. Geol. Soc, xxiii 

 (1867) ; and Hull, Geol. Mag., Dec. II, V, may be consulted. 



' GeDINNIBN ' OF THE CONTINENT. 



These beds have been described by many eminent geologists in 

 their respective countries. Among them may be mentioned Gosselet 

 and Barrois in Prance ; Dumont, Dewalque, and Malaise in Belgium ; 

 Von Dechen, Koch, Kayser, Holzapfel, Eothpletz, and Lessen in 

 Germany. To Professors Gosselet, Barrois, Kayser, and Holzapfel 

 I am gratefully indebted for personal guidance and much information. 



Speaking generally, the beds comprised in the Continental 

 Gedinnien in descending order are as follows : — 



1. Slates, mostly variegated and phyllitic, underlying the ' Taun- 

 usian,' with fish remains either in the base of the latter or in the 

 slates themselves. 



2. Arkose or Felspathic Grits, locally, and more especially on the 

 south border (Taunus, etc.), sericitic and metamorphous. 



3. Conglomerates with pebbles of more ancient rocks in a felspathic 

 and quartzose matrix. These conglomerates seem to follow the 

 sinuosities of the old coastline, and only appear intermittently ia 

 their original form, being as a rule much altered by hydrothermal 

 action induced by pressure and folding. The latter subject has been 

 treated at great length by Lossen.'' 



A comparison of this description with that given by Hull- of the 

 Dingle and Glengariff Grits of Ireland may be of interest. He 

 records — 



1. Conglomerate. 



2. Eed and green grits. 



3. Purple slates passing unconformably below the (? Lower) Old 

 Eed of Cork. And he suggests that the Foreland group of North 

 Devon, of which the base is not seen, described bj' Jukes -^ as "thick 

 massive grits of green and red colour, with purple slates similar 

 to many j^arts of the (? Lower) Old Eed of the south-west of 

 Ireland," corresponds with these grits. 



The Coenish Gedinhian. 



Turning now to the Cornish beds, and commencing east at Looe, 

 where the variegated slates of the Upper Gedinnian are in undoubted 

 apposition to the beds referred to by Collins^ as Upper Silurian, 

 and by Ussher '" inadvertently as ' Gedinnien,' but which I consider 

 are undoubted!}' Taunusian of the ' Siegener Grauwacke ' facies, as 

 evidenced by the following typical fossils found by myself and 

 others : — 



1 Z. deutsch. Geol. Ges., 1867, 1877, 1883. 



2 Geol. Mag., Dec. II, V (1878), p. 529. 

 2 Additional Xotes (Dublin, 1867). 



* Joum. Eoy. Inst. Cornwall, vui (1884), p. 167. 

 = Summary of Progress Geol. SuiTey for 1900. 



