382 Correspondence. 



floor of Thor's Cave, at about nine hundred and fifty feet above the 

 sea-level. 



I do not understand Mr. Green's hesitation to admit that the sea 

 covered the Derbyshire Limestone Hills at the Glacial epoch, for I 

 read in the valuable Ordnance Memoir of the country round Stock- 

 port, Macclesfield, Congleton, and Leek, by Messrs. Hall and Green, 

 and with the paragraph itself bearing the initials A. H. G., that 

 " In an outlying patch of sand and gravel about three miles from 

 Macclesfield, on the Buxton road, at a height of about twelve hun- 

 dred feet above the sea, Mr. Prestwich found shells; and Mr. 

 Sainter tells me that he has collected there Turritella, Cardium edule, 

 and others." Now the point on the Axe Edge range here indicated 

 is only about sixteen miles from Weaver, and the highest tops of 

 the Weaver range are not more than about twelve hundred and twenty 

 feet above the sea; the Weaver Clays and the Boulder Drift, the 

 subjects of the present communication, lying at from one thousand 

 to one thousand and fifty feet. 



We have not yet found shells in the drifts of the neighbourhood ; 

 but we have every other proof that can be desired of their marine 

 origin. 



The chief geological interest that attaches to the " Weaver Clay " 

 deposit is, that it proves a submersion of this part of the country 

 at some period between the Triassic and the Boulder-clay epochs, at 

 which latter period our hills were undoubtedly again sunk beneath 

 the sea. I am, Sir, Yours faithfully, 



Edwin Brown. 

 BuRTON-upoN -Trent. 



\2th July, 18Q7. 



THE LOB-WORM EPOCH. 



To the Editor of the Geological Magazine. 



SiK, — Mr. Baily (Figures of Characteristic British Fossils, p. 12) 

 tells us that the only remains of animals in the Cambrian rocks (the 

 oldest fossiliferous British strata) are those of worms ; and (p. 3) 

 that these worms were " allied to the recent lob-worm," It is true 

 that he remarks (p.l2) that "it has been argued, and with reason, 

 that this apparent paucity of organic remains may have arisen from 

 the nature of the deposit . . . and that there may have been a more 

 varied assemblage of life during this epoch ... as this, however, is 

 necessarily conjectural, much importance cannot be attached to it." 

 Now is the negative argument not also " conjectural ? " and is it not 

 a most absurd conjecture that because in certain marine strata, in a 

 certain place in England, signs of no life are found save that of 

 worms that in the "epoch" or time when those strata were formed 

 no animals existed on the terraqueous globe save worms ? Is this 

 not " conjectural ? " and most abs-urdly conjectural ? Continents 

 from the denudation of which the Cambrian strata were formed 

 must have existed for countless millions of years. And were these 

 continents, and the land, and the water, of the whole terraqueous 

 globe uninhabited, except by marire lob-worms? This is a curious 



