E. W. Binney. 457 



In fact, we have in the floor a fine rich soil, well calculated to 

 have produced a luxuriant crop of vegetation, full of immense 

 numbers of Stigmaria ficoides, now proved by the trees of St. 

 Helen's and Dukinfield to be nothing more than the roots of 

 Sigillaria. 1 So their presence under the seams of coal is now 

 fully accounted for, being merely the roots in situ of the forests 

 of Sigillaria, that have chiefly formed the beds of coal found lying 

 above them. These fossils are of great value in accounting for 

 the true formation of coal seams, and must for ever do away with 

 the drift hypothesis, so far as concerns those seams in which they 

 are found in the floors, and establish the rival theory which 

 attributes the formation of coal seams to vegetable matter, grown 

 upon the identical places where it is now found.' 



Page 175. * Although the stems of Sigillaria have been generally 

 noticed in the roofs of coal seams, it is by no means to be inferred 

 that they are not to be found in other portions of the carboniferous 

 strata. They no doubt have been found more frequently in the 

 roof than other places ; but that part can be better examined 

 than other strata in a mine. The fossil trees at St. Helen's, all 

 Sigillaria, were four in number, and occurred in a deposit of grey 

 indurated silty clay, lying about eighteen yards two feet above a 

 foot coal, and fourteen yards one foot under a yard seam ; the 

 bases of the stems lying about eight feet above a white gritstone 

 rock, and the stems proceeding upwards in the warren, which 

 was completely traversed, as far as it could be traced, by Stigmaria 

 ficoides ; so if the whole of the rock had been on in the quarry, 

 the stems would probably have reached up to the Roger seam of 

 coal.' 



Page 177. * Lately has been discovered in the floor of the 

 Victoria Mine, Dukinfield, near Manchester, at the depth of 

 eleven hundred feet from the surface, a magnificent specimen of 

 Sigillaria, which exhibits in the stem the respective characters of 

 the species pachyderma, reneformis, and organum, and true 

 Stigmariae traced eighteen or twenty feet as its roots. The stem 

 was about two feet high, and could not be traced into the coal 



1 Phil. Mag. for March 1844, and October 1845 ; also Quarterly Journal 

 of the Geological Society for Nov. 1846. 



