1868.] nOLL SOUTH DEVON and east CORNWALL. 429 



collection ; and a scale from Meadfoot is fi^^ircd by Prof. Phillips 

 (Pal. Fos. pi. 57. f. 256), and referred to Holoptyclilus, which has 

 also, judging from the figure, very much the appearance of Phil- 

 lolepis. 



It is less easy to ascertain the relations of the limestones to the 

 north and east of Totnes, although there is no reasonable cause for 

 supposing that these calcareous masses are other than portions of 

 the same range of limestones. This arises partly from the extreme 

 difficulty there is in getting reliable evidence respecting the dip of 

 the beds, as much of the Kmestone exhibits no true bedding, and 

 the lamination of the slates cannot always be relied upon. 



The limestones do not afford much assistance. It is frequently 

 extremely difficult to distinguish the bedding from the often very 

 regular joints and planes of cleavage ; and a bed of fossiliferous rock 

 included between others that are devoid of fossils will sometimes 

 show a true dip quite at variance from the apparent one. More- 

 over the limestones are sometimes much fractured and contorted ; 

 and in that case very little reliance can be placed upon a few local 

 observations, which may yield very conflicting results. The junk- 

 like termination of some of the limestones is another source of per- 

 plexity, their relation to the slates being such as to make it appear 

 that, in the movements to which the rocks have been subjected, the 

 limestones have been, as it w^ere, dislocated from the slates, so that 

 the former are bounded by what are virtually lines of fault. 



It would appear, however, that higher rocks, which occupy a 

 synclinal trough that trends up from Plymouth Sound by Halberton 

 to the vicinity of Totnes, are thrown down by faults, one of which 

 runs up from Sandwell Park, by Whiteley and Colt, to the Dart south 

 of Dartington House, and is continued thence across the railway 

 south of Forder Bridge, and another, skirting the limestone of 

 Boston, is continued N.N.W. towards Bow Barn. The result of 

 this downthrow has been to push the southern extremity of the 

 Dartington limestone round to the north-west, and the Barton and 

 Bunker Hill limestone to the eastward. The evidence of the former 

 fault is to be seen in proceeding along either of the turnpike -roads 

 from Totnes to Skinners Bridge. We there find similar thick 

 slates to those which occupy the country between Totnes and Ash- 

 springton, to be continued nearly to Colt with a south-easterly dip ; 

 but at Colt the dip of the slates conforms to that of the overlying 

 limestone at Skinners Bridge, and is to the north-west, A third 

 fault follows the bed of the Dart from Totnes to the south of Alla- 

 beer — the thick slates which strike up to the river at right angles to 

 the stream with a southerly dip abutting against thinly laminated 

 argillaceous slates which, with a variable dip more or less to the 

 eastward, occupy the low ground on the opposite bank, near 

 Weston. This fault carries the country on the east of the Dart 

 somewhat to the southward. Another fault, extending from Long- 

 combe Cross to True Street, bounds the limestone of Berry Po- 

 meroy on the south. The limestone dips to the north, while 

 the red slates on the south of it dip in the contrary direction 



