34 CORNISH POST-TERTIARY GEOLOGY. 



Further eastward the vegetable bed was 4 feet thick, consisting 

 of branches and twigs of hazel and birch in the upper part, and of 

 leaves and woody fibre in the lower part ; it extended to the eastern 

 Cressets rocks.^ 



The vegetable stratum generally rests on clay slates, or on a Ijluish 

 sand, and in one place on a mass of gravel. At Huel Darlington 

 Mine, in Marazion Marsh, Mr. Came obtained the following section, 

 in a pit near Marazion River : 



1. Slime (? river) tjravel, and loose ground 



2. Peat, with minute woody fibre (fit for fuel) 



3. White sand, with Cardium edule 



4. Oak and hazel trees lying in all directions ; hazel nuts loose 



and on their branches ; a piece of oak, shaped as if for a boat 

 keel 



5. Solid hard peat, closer than the upper bed (good for fuel) ... 



6. Alluvial tin ground on clay slate rock 



In a part of Huel Darlington Mine, where the tin ground was at 

 a higher level, bed 3 of the preceding section rested directly on the 

 tin ground. 



Mr. Carne considered bed 4 to be a continuation inland of the 

 Mounts Bay Submerged Forest, the difference in level between them 

 being small. 



Traces of submarine forests are said to occur at Perran Forth, St. 

 Colurnb Forth, and Mawgan Forth." 



The forest near Fadstow, on Dunbar Sands, has been described by 

 Mr. Henwood.^ 



Mr. S. R. Fattison* notes the discovery of 20 feet of soil, between 

 high- and low- water mark, at Maer Lake, near Bude Haven ; ti-ees 

 of large size, and roots apparently in situ in dark clay, have been 

 found; also a bullock's horn 4 feet long and 18 inches in circum- 

 ference, and a stag's horn 5 feet in length. 



1 Dr. Boase (Trans. Roy. Geol. Soc. Corn. vol. iii p. 172) describes the forest 

 stratum, traceable on the seaward side of the "West Green Sand Bank for 200 yards 

 in width, at low water, from Larrigan rocks to Newlyn, as " trunks and branches 

 of hazel, alder, elm, and oak (with leaves and the elytra of beetles), lying in all 

 directions; the larger ti'unks lie N.E. and S."W., they are split and frequently 

 perforated by Pholns daetyliis. 



2 De la Beche, Report on Geology of Cornwall, etc., p. 419. 



3 Fortieth Ann. Rep. Roy. Instit. Corn, for 1858. 

 * Trans Roy. Geol. Soc. Corn. vol. vii. p. 34. 



