28 THE GEOLOGICAL AGE OP CENTRAL AND WEST CORNWALL 



liglit has been thrown upon it, and, on the whole it may be said 

 to remain in statu quo. so far as the evidence from Palaeontology 

 is concerned. 



The *' Fowey Beds " have a remarkably regular strike to the 

 S.S.E., and a N.N.E. dip, from the Gribben Head to Polperro — 

 a distance of nearly nine miles. How much farther to the* 

 eastward they extend I cannot say, but probably they may reach 

 to Looe, for many similar fish-remains have been found there. 

 Inland, the same beds may be traced between the Bodmin and 

 Hensbarrow granite masses nearly up to Bodmin. The whole 

 area covered by these rocks in this part of Cornwall cannot be less 

 than 80 square miles. t 



No very extensive " strike faults " are known between Fowey 

 and Polperro, except that which forms the iron lode at Eestormel. 

 This runs nearly N.S., and has an eastward underlie, like most 

 of the great cross-courses of Cornwall. The downthrow here 

 cannot exceed a few hundred feet. As the north-eastward dip 

 is observable for over six miles, and averages certainly not less 

 than 26°, the total thickness of the " Fowey Beds " can hardly 

 be less than two miles. 



This great series of beds is mostly of a slaty character — a dull- 

 greyish brown being the prevailing colour. In some parts, — as 

 in several quarries in the parish of St. Yeep, these pass into a 

 yellowish or reddish sandstone, containing numerous fragmentary 

 fossil markings, among which are a good many echinoderms, 

 sometimes tolerably well-preserved. 



Westward the Fowey beds are cut off by the Hensbarrow 

 granite, but they appear to rest upon Lower Silurian rocks in 

 the neighbourhood of Mevagissey, and perhaps also at the 

 Blackhead. To the northeast they appear to underlie the beds 

 with an E.W. strike, which fringe the southern side of the 

 Bodmin granite, and these latter, having been lifted up previous to 



* This dip is marked correctly in the Survey Maps but by what is probably a 

 slip of the pen, the strike is said to be N.N.E. in the text of De la Beehe's 

 " Report," (p. 80.) 



f Hitherto the discoveries of fish remains have been mainly confined to the 

 coast sections, inland exposures of the strata being somewhat rare, and inland 

 observers still rarer. Mr. Pengelly, however, has found '"very excellent specimens" 

 in a light-coloured schist at Cliff in the parish of St. Veep. (Trans. Boy. Qeol. 

 Soc. Corn., 1850, p. 80.) 



