APPENDIX. 



Since the preceding pages were put into type, probably the finest example of a 

 fully developed Stigmaria ficoides yet seen has been discovered and has come into 

 my possession. Mr. Murgatroyd, the intelligent proprietor of a large quarry of 

 Carboniferous Sandstone at Clayton near Bradford, in Yorkshire, removing some 

 stone by means of dynamite, found amongst the exploded materials some frag- 

 ments of a Stigmaria. Seeing that the root extended into the undisturbed rock, 

 with a thoughtfulness highly creditable to him, he ceased to employ explosive 

 materials, and had the overlying stratum removed with great care. The result 

 was the revealing of the magnificent specimen represented in Plate XV. This 

 representation is a copy of a beautiful photograph taken by Mr. R. C. Clifford, a 

 skilful young professional photographer, residing at Westgate, Bradford, to whom 

 I am indebted for permission to use the photograph in illustration of this memoir. 

 The photograph has been reproduced by the Automatic Engraving Company, 

 of Willesden Green, near London. The tree stands upon a flat stratified surface, 

 composed of an arenaceous shaly bed, which is abundantly permeated by the 

 remains of its disorganised rootlets, and upon which its magnificent roots are 

 spread out with undisturbed regularity. The overlying stratum is a hard sandstone, 

 identical with the inorganic material of which the roots themselves consist. It is 

 obvious that the entire base of the tree became encased in a plastic material, which 

 was firmly moulded upon these roots whilst the latter retained their organisation 

 sufficiently unaltered to enable them to resist all superincumbent pressure. This 

 external mould then hardened firmly, and as the organic materials decayed they 

 were floated out by water which entered the branching cavity ; at a still later 

 period the same water was instrumental in replacing the carbonaceous elements by 

 the sand of which the entire structure now consists. It is obvious that we have 

 not got the ultimate divisions of the roots in their entire length. Their extremi- 

 ties have failed to be preserved, from a reason given at p. 29. Still the roots, as 

 seen in the plate, extend 29 feet 6 inches from right to left, and 28 feet in the 

 opposite direction. 



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