ETHEETDGE^DEYONIAN" EOCKS AXD FOSSILS. 611 



slaty masses can hardly be conceived, even on lithological grounds 

 alone, than in the rock-masses of these two areas tuhen carefully ex- 

 amined. I have now to show, if possible, that there is no uncon- 

 formity in Morte Bay between the Mortehoe and Woolacombe Slates 

 and the Pickwell-Down Sandstones, and that they here insensibly, 

 through lithological changes, graduate into the hard red grits and 

 sandstones at Potter's Hill, Croscombe, and Pickwell Down, as they 

 do at AVivehscombe and intermediate points. Up to the village of 

 Yroolacombe, north of the stream, the slates are seen in places on the 

 shore under Tracey and Potter's Hill dipj^ing 60° and 70° S. The 

 Woolacombe and Osborough valley was carefully searched ; and no- 

 where down the stream, which here runs over, and cuts through the 

 strike of the beds, or to the east, at Dean Mill, where they are cut 

 across by another rivulet, and dip 70° S., did I detect any inversion, 

 notable disturbance, or alteration of dip; more than that, the grada- 

 tion into the thicker beds of Potter's Hill and Higher Bullen is traced 

 through a series of red gritty slates and fissile sandstones dipping 

 50° S., and resembling in all particulars the junction at and passage 

 under Main Down, west of Wivehscombe &c. ; the small quarry on 

 Potter's Hill showed the same lower thin-bedded red grits dipping 

 45° S. ; on the strike of these beds, east, across the hill, and in a quarry 

 at Higher Bullen, the same series dip 60° S. Descending to the shore 

 under Potter's Hill, and at Tracey, we now take them in upward suc- 

 cession ; the reefs of grey fissile slates, with rusty or decomposed bands, 

 that crop out on the shore immediately west of the Kiln at T^^'oola- 

 combe, are the same that occur in the Tracey and Osborough valley, 

 and are immediately succeeded by the Potter's Hill red group. On and 

 along the shore between AVoolacombe and Baggy Point twelve groups 

 or reefs of red, claret, grey, and green micaceous sandstones crop 

 up, and the recent marine sands of Morte Bay (Woolacombe Sands) 

 cover up their inclined edges and continuous dip. Every bed visible 

 along the shore, and composing this series of sandstones, was mea- 

 sured, the interspaces (covered by the sands) were paced, and careful 

 notes made upon the whole magnificent section up to the overhang- 

 ing abrupt northern face and escarpment of Baggy Point, where, 

 without a trace of movement, break, or unconformity, the passage 

 into the true fossiHferous Ui3per Devonians is complete*. It is both 

 superfluous and unnecessary to describe the Morte section in detail ; it 

 speaks for itself; neither above or at the top of the Upper Old lied 

 Sandstone at Yention and Pulsborough, nor at the base at Tracey or 

 Osborough is there any evidence of dislocation, or any trace of a fault. 

 6. Conclusions relative to the Middle Devonian or Ilfracomhe Group 

 of West Somerset and North Devon. — (1) Whether the red grits and 

 sandstones of the Hangman should be classed vnth the upper part 

 of the Lower Devonian or Lynton group, or should constitute the 

 natural base of the Ilfracomhe slates, it may be difiiculr, if not 

 impossible, to determine, no fossils occiUTing throughout the whole 

 series until we reach the upper gritty beds of the Little Hangman, 



* See Mr. Salter's valuable paper upon the Upper Old Red Sandstone of 

 INorth Devon and South ^Yales, Quart. Journ. Geol. Soc. xix. 1863. 



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