Clement Heid — Culm-measures near Chudleigh. 455 
„ spinosa, Phil. 
Natica ? 
Acroculia vetusta, Phil. 
Murchisoiiia angulata, Phil. 
Euomphahts serpens, Phil. 
Macrocheilus ? 
Pleurotomaria cirriformis, Sby. 
Prof. Phillips and Mr. Jukes suggested the existence of a fault, 
and a detailed examination of the ground has enabled me to trace 
a dislocation which will without difficulty account for the apparent 
unconformability. 
Unfortunately sections of the junction of the Culm-measures and 
Devonian Limestone are rare, but in the road south of Lewell 
House, near Chudleigh, we have an exposure which has every 
appearance of a passage. The upper part of the Limestone is seen 
to become more and. more shaly, then to pass into alternations of 
shale and limestone; and gradually grit, at first fine grained, replaces 
the calcareous beds. Still higher there is thick-bedded sandstone 
like that in the lower part of the Culm-measures of Ugbrooke Park. 
The upper part of this section is not clearly exposed, though it 
seems to indicate a passage. 
At Lower Dunscombe Quarry the Limestone again passes into 
limestone-shale containing Clymenia valida and C. striata (as identi- 
fied by Mr. Etheridge). Unfortunately the junction with the Culm- 
measures is not exposed; but as far as can be judged from the stones 
in the adjoining fields, it is similar to that shown in the last section. 
It is noticeable that the species of Clymenia have not been found in 
the solid limestone, but only in the few feet of calcareous shales 
above it. 
A more difficult question has arisen from the abrupt ending of the 
Limestone on the west of Chudleigh and its sudden replacement by 
Culm-measure shales. The small patch at Waddon Barton is nearly 
horizontal, and entirely smrouuded by green and purple Devonian 
slates ; . the isolated position of this limestone is caused by de- 
nudation, and a sliglit flexure of the beds will connect it with the 
main mass. A short distance to the west a fault runs in a north 
and south direction, throwing down Culm-measures against the 
slates ; this fault I have traced northward to Whiteway House, 
where the Limestone and Culm Shales are thrown together. The 
fault then disappears beneath the Triassic rocks of Haldon, ap- 
parently without affecting them. To the south the dislocation can 
be traced to near Lower Herkley, beyond which I have not ventured 
to continue it, as there are only slates and shales for guidance. 
Mr. Godwin-Austen, in bis “ Geology of the South-east. of Devon- 
shire,” mentions a well dug at the house on the west side of Chud- 
leigh rock. This showed about fifteen feet of horizontal cai'bonaceous 
shales and sandstones resting on highly inclined claret-coloured slates 
dipping in the same direction as the Chudleigh Limestone. Mr. 
Austen considers tbat this is an instanoe of unconformability ; but on 
quite independent evidence, and before I had noticed the account of 
this well, I had been led to trace the fault through this exact spot. 
A considerable bade to the fault will account for all the appearances 
in this and some other sections noticed by Mr. Austen and Sir Henry 
De la Beche. 
