Cornwall and South Devon. 341 



and near the huge dyke of porphyry at Cawsand, a succes- 

 sion of dips from south to south-south-west, south-west, and 

 finally west, mark the angle from which its strike deviates to 

 St. Anthony, Sheviock, Hessenford, Bin-Down, St. Keyne, 

 and from thence follow the lofty ridges of heather-brown hills 

 by Pinnock common, Five-Barrow hill, Bodmin downs, St. 

 Breocks and Denzel downs to Watergate bay : from this nearly 

 central line, its beds on the west roll out to the southward in 

 endless repetitions, by long undulations or rapid flexures as 

 far as the granite of St. Ives on the north channel, and over 

 the whole Peninsula to the sea on the south, from Pencarrow 

 point east of Fowey, to Falmouth, the Lizard serpentine and 

 hornblende rocks, and the granite of Penzance. 



Mr. Peach informs me that with the liberal loan of books 

 by the President, Sir Charles Lemon, he has been able to 

 identify the following Orthides which he has discovered in the 

 vicinity of Gorran, viz. Orthis lata, orbicularis, alternata, 

 canalis, Jlabellulum, testudinaria, interlineata, sordida, pli- 

 cata. Five of the above species have also been found in the 

 lower beds of the Palaeozoic rocks of Wales, one from the 

 higher beds, and the remaining three, according to the lists 

 of Professor Phillips and Mr. Sowerby, appear as yet to be 

 peculiar to Devon and Cornwall: I feel assured that my col- 

 lection will add some new and remarkable species to the above 

 when described (as I hope they shortly will be) by that ex- 

 cellent naturalist Mr. James Sowerby. 



The remains of fish which occur so plentifully in the upper 

 series, are apparently as rare in this, as fossil mollusks, &c. 

 are in the other. Sir H. De la Beche has however found a 

 specimen at St. Columb Porth, and Mr. Phillips another at 

 Meadfoot sands near Torquay, — both in this formation*. 



No. 2 killas is distinguished from the former by being an 

 entirely independent series throughout, except on its upper 

 and lower confines, along which it passes by alternation and 

 mineral gradation into Nos. 3 and 1 : its mean bounding line 

 from No. 3 is just above the range of the Plymouth limestones, 

 or their equivalent gray calcareous andfossiliferous slateswhich 

 supply their intervals of continuity : these are immediately 

 succeeded below by an enormously-thick suite of slates, 



* See Phillips's Palaeozoic Fossils of Cornwall, Devon, &c. I have found 

 portions of fish-bones as low down as the Linton slates, and eoprolitic 

 looking bodies in the Trilobite slates near Barnstaple, and Mr. Parker, jun., 

 late of Exeter, found a beautiful tooth in the Posidonia limestones of the 

 Coddon hill grit series at Doddiscomb Leigh, north of Chudleigh, which 

 Prof. Owen pronounced to belong to the Rhopalodon, a genus of fishes 

 hitherto found only in the Urals. 



