248 W. A. E, Ussher — Permian in Devonshire. 



Becutive horizons. In the Teignmouth breccias with numerous 

 fragments of claystone porphyry, quartz porphyry, etc., he detected 

 a strong resemblance to the Rothliegende (Upper Soterner) of the 

 Nahe, above the volcanic horizon (Grenz schichten). In the Volcanic 

 rocks of the Exeter and Ciediton areas he recognized the equivalents 

 of the Grenz schichten (Middle Soterner). Herr von Reiiiach also 

 pointed out to me the similarity presented by some of the thick even- 

 bedded red and whitish sandstones intercalated with marls to the 

 east of Exraouth, to the Upper Bunter Sandstones of the Moselle, 

 recalling to my mind sections I had seen near Treves and in the Eifel. 

 On the 10th of last February Herr von Reinach wrote me as 

 follows : — " Professor Biicking had the kindness to determine the 

 melaphyres and tuffs I brought with me from the environs of Exeter. 

 As I do not intend to publish these facts, I authorize you, also in the 

 name of Professor Bucking, to make use of this communication. 

 You know that we have at the Nahe — (1) Melaphyres in the Older 

 Riithliegende which are only intrusive ; (2) Melaphyre Covers 

 (Melaphyr decken) which we have only in the vSoterner (Grenz 

 schichten) of the Rothliegende. The Grenz Melaphyre has been 

 divided by Lossen into Upper, Middle, and Lower, which types are 

 generally the same throughout the Nahe district." Prof. Biicking's 

 identifications are as follows : — 



Spencecombe, Knowle Hill (Crediton Valley) { St^^Met^iy'r with' 01^^^^^^^^ 



Posbury, near Crediton ) Melaphyr with Olivine. 



rocombe, near Lxeter ) ^ •' 



Duncbideock, between Exeter and Chudleigh. — Melaphyr with Olivine and Bronzite. 

 Yeotou, near Crediton. — Tuff. 



Herr von Reinach adds : ' The Dunchideock Melaphyr is identical 

 with our type of the uppermost Melaphyr roof zone (Dach zone) of 

 the environs of Krentznach on the Nahe.' " 



Although the detailed mapping of the eruptive rocks associated 

 with the New Red of Devon was completed about fourteen years 

 ago, I have published nothing specially on that subject, certainly 

 not from lack of materials. In 1876 Mr. Rutley visited all the 

 chief localities with me, and determined the rock for the Geological 

 Survey ; these determinations have been lately confirmed by Dr. 

 Hatch, and they agree with the determinations of Prof Biicking; 

 of this Herr von Reinach was not aware, but the fact rather enhances 

 than lessens the importance of the communication he has so kindly 

 authorized me to impart. 



If we assume the correlation of the New Red volcanic rocks 

 with the Grenz-schichten as established, the probable correlations 

 with the Nahe section might be as follows : — 



Dawlish breccias Upper Rothliegende. 



Teignmouth breccias Wjower Rothliegende. 



Basalts (local) ) (SiJterner beds with 



"Watcombe and Petitor conglomerates... ) volcanic rocks). 



It must, however, be borne in mind that no correlations framed 

 on a partial, or even intimate acquaintance with the South Devon coast 



