512 ME. W. A. E. USSHER ON THE DEVONIAN 



slates are blackish by the highroad west of Abbotskerswell, and 

 they contain lenticular limestone (resembling that in the little 

 quarry at Livaton) at 25 chains south of liydonball Cross. I have 

 no hesitation in regarding these beds as Upper Devonian, probably 

 representing the Knollen-Kalk and Entomis-slates. 



As the Cypridinen-Schiefer has been traced by its characteristic 

 lithological character and by the presence of Entoniis and Posido- 

 nomya at Newton-Abbot, Highweek, and Houghton, the repre- 

 sentation of the Goniatite-beds between it and the limestones and 

 diabases of Bickington on the one side, and the limestones of 

 Bradley "Woods and AVest Ogwell on the other, is almost demon- 

 strated. 



As the occurrence of Upper-Devonian beds between these lime- 

 stones is established by the discovery of the Cypridinen-Schiefer 

 (Entomis-slates), Mr. Champernowne's correlation of the Ashburton 

 and Ogwell limestones is demonstratively proved, by synclinal, not 

 anticlinal structure, as was supposed. This synclinal is occupied by 

 red, pale greenish, and grey slates, in which fossils are extremely 

 rare. Ey lithological character no line can be drawji in this slate - 

 area. 



Red slates resembling those of Saltern Cove bound the Bradley- 

 Manor limestone on the north, and can be traced, with varying 

 characters, to the Lemon Valley opposite East-Ogwell Mill. Near 

 East-Ogwell Mill they contain limestone plaques and are very 

 similar to the slates of Silver Cove ; from the Mill these slates, 

 varying to greenish and dark-grey tints, may be traced southward 

 through East Ogwell, where they contain Entomis, and round the 

 southern termination of the Eamsleigh limestone. 



Following round the limestone border from Bradley Earm to 

 Denbury, we find a gradually broadening area of grey slates 

 separating the red and green Upper Devonian, which are continuous 

 through Woodland, from the limestone. These slates, traced south- 

 ward, are found to represent the Middle-Devonian limestones of the 

 Ipplepen and Plymouth districts ; they contain shaly limestones 

 here and there near Staverton. 



Here, then, we have the Middle- and Upper-Devonian types de- 

 scribed in my paper * on the Tavistock district, and an analogy is 

 presented to the Morthoe and Ilfracombe slates of North Devon, 

 and the red slates of the Pick well-Down series. 



In the area between Newton-Abbot and Bickington, at Wrigwell 

 House, 2j miles west of Newton, in pale greenish slates I dis- 

 covered traces of Gouiatites, one though indistinct being perfect, 

 although, alas, quite unidentifiable. In the same slates I obtained 

 small OrtJiocerata or Bactrites. All Dr. Kayser says about these 

 fossils is " scarcely recognizable, but by the matrix probably 

 Goniatite-slates ( = Biidesheim)." 



Near Metley, at about half a mile south of Wrigwell House, and 

 near Killinch, about half a mile west of Metley, I detected traces of 



* Trans. Devon. Assoc. 1889. 



