494 MR. AV. A. E. USSHER ON THE DEVONIAN 



§ IV. Lower Devonian, 



1. Torquay Area. — Up to the year 1889 the record of the 

 occurrence of Lower Devonian in South Devon is confined to the 

 Torquay promontory. (See Map, Fig. 1, opposite p. 490.) 



In that promontory two divisions of the Lower Devonian had 

 been recognized, the Upper (Lincombe and Warberry beds) con- 

 sisting of red sandstones and grits with shales, the Lower (Mead- 

 foot beds) of irregular bluish-grey slates with hard grits. 



Mr. Champernowne discovered Homalonotus on the east side of 

 Lincombe Hill by the N'ew Cut, " in some rod finely-sandy or silty 

 beds, interstratitied with grits. The beds are traversed by a coarse 

 cleavage dipping south, which usually ignores the hard grit-bands. 



"Wo may call them .... the Lincombe, Warberry, and Smug- 

 gier's-Cove grits .... Within a hundred yards west of the spot 

 where the specimen occurred, this subgroup becomes mottled with 

 light colours, brown grits appearing, and passes down into the 

 ^leadfoot series. . . . The grits of the Meadfoot series are less 

 distinctly quartzose, and are more tenacious, requiring heavier 

 hammers. If we imagine this lower group coloured red, it is 

 difficult to say whether, on purely palaeontological grounds, they 

 would be separated from the upper ; but it is probable they might 

 be. The buff and brown weathering of the ^Feadfoot beds disappears 

 with depth, as the heaps shot out from the Torquay drainage- works 

 show, grits and shales alike being of a blue-black tint ; whereas red 

 or ])urple beds, as a rule, are so both at the surface and in depth. 

 In tlie passage-beds described above, I hold that we have a horizon 

 corresponding in general terms with that between the Hangman 

 and Lynton groups of jSTorth Devon .... If now we look abroad, 

 we seem to gain some insight into the occurrence of red sandstones 

 of marine origin on the same horizon in the Devonian rocks. In 

 the Eifel district the ' Homalonotus Sed Ulagstones,' so named by 

 Murchison, " occupy a horizon high in the Lower-Devonian beds, 

 scarcely removed from the base of the Calceolen-Schiefer, and the 

 bulk of the Coblentzian or Ahriau, the chief home of Pleurodic- 

 tyum prohleinaticum (though this mud-loving Favositid ranges 

 liigher in the series) lies below them " *. 



The Lincombe and Warberry beds occupy the highest land in 

 the Torquay promontory ; in their extension to the coast at Smuggler's 

 Cove they are faulted on the north and south, but on the hill 

 above Kilmorey they occur in an isolated patch. 



These grits do not appear on the coast in unfaulted relation ; 

 and, as red Eifelian shales and shaly limestones with Calceola 

 directly underlie the limestone of Daddy-Hole-Knoll, their absence 

 between this and the Eifelian slates and limestones of Hope's Nose 

 is only to be accounted for by an extensive fault cutting them out, 

 unless we are prepared to admit that they underlie the Meadfoot 

 beds, or occur impersistently in the upper part of that series. 



* Geo!. Mag. 1881, p]). 487, 488. 



