488 MH. W. A. E. USSHKR ON THE BEVONIAX 



the Devonian faunas, and the extraordinary persistence of homo- 

 taxeous horizons, such as those characterized by Stringooephalus^ 

 Rliy iivlionella cuhoides, and Gonlatites, at the same time presenting 

 us with the varied evidences of stratigraphical succession. 



The disturbances to which Prof. Williams refers, the distortion of 

 fossils in consequence, and the paucity of localities rich in charac- 

 teristic fossils, renders South Devon a most unprofitable field to the 

 casual investigator, whilst depriving the stratigraphist of the only 

 means of piecing the scattered details into a connected whole. 



The late Mr. J. E. Lee's * discoveries of the Biidesheim and Adorfer- 

 Kalk faunas at Saltern Cove and Chudleigh proved that the Gonia- 

 tite fauna had extended to Devonshire ; but the faulted occurrence 

 of the beds containing it precluded the observation of their true 

 position in the formation. 



The South-Devon limestones were, with two or three exceptions, 

 regarded as Middle Devonian, and the presence of Lower Devonian 

 was only proved in the Torquay Promontory. 



The old 1-inch Ordnance Map on which De la Beche, Godwin- 

 Austen, and subsequently Dr. Harvey Holl and Champernowne, 

 were compelled to record their observations on the stratigraphy of 

 South Devon is much too small to note minutiae which have the 

 most important bearing on the question. 



Dr. Hollf, in 1868, placed both the Plymouth and Paignton 

 sections in the wrong sequence, through the acceptation of inverted 

 dips as natural evidences of superposition ; yet his sections account 

 for the position of many of \h.Q types which he correlated by 

 inverted plication. The succession he advocated in descending 

 order is : — Staddon and Cockington grits, slates, limestones. He 

 likewise endorsed Godwin-Austen's view that the limestones of 

 Ashburton were a lower series than those of Newton and Ipplepen. 



During a re-survey of portions of the country around JNTewton- 

 Abbot and Ton^uay in 1874-75, my colleague, H. B. Woodward J, 

 arrived at the conclusion that the Devonian rocks occurred in 

 descending order as follows : — 



Limestones. 



Slates. 



Eed Sandstone (of Cockington). 



When this general succession was published in 1876, it was 

 adopted by Mr. Champernowne as affording "• the clue to unravel 

 the country." 



Mr. Champernowne §, in " i^otes on the Devonian and Old lied 

 Sandstone of North and South Devon," gave the true succession in 

 sections of the Mudstone-Bay coast. " This," he says, " brings the 

 Ued Sandstone into direct and natural relation with those of 

 Cockington, the Warberry, Lincombe, &c. at Tonjuay, irhich are 



* Geol. Mag. 1877, p. 100, and 1880, p. 14o. 

 t Quart. Journ. Geol. Soc. vol. xxiv. p. 400. 

 + Geol. Mag. 187(5, p. 576. 

 § Ibid. 1878, p. 193. 



