Mr. Tate on the Geology and Archaeology of Beadnell. 101 



The sandstones and shales associated with the coal seams 

 contain relics of the vegetation of the Carboniferous Era ; a 

 few Sigillarioe and many Stigmaria Jicoides appear in these 

 beds. One interesting specimen of a Sigillaria, which was 

 laid bare, when quarrying the sandstone in 1853, deserves a 

 more particular notice. Though but a fragment, it was 6 

 feet in height, and 2 feet 2 inches in diameter at the lower 

 end, and 1 foot 9 inches at the higher ; it stood perpendicular 

 to the strata which dip south-east 15** and its inclination to 

 the horizon was 75**. The lower extremity terminated ab- 

 ruptly on the surface of slaty sandstone beds, but the outcrop 

 of the rock in which it was embedded prevented our knowing, 

 how far upward it extended. Over the surface was a thin 

 carbonaceous coating, being the bark converted into coal ; 

 but the interior was replaced with sandstone and retained no 

 structure. It had, however, the rude flutings which dis- 

 tinguish the casts of Sigillariae ; and it appeared to belong 

 to the species Sigillaria organa. The sandstone in which 

 it stands consists of several beds ; and the lines of stratifi- 

 cation distinctly pass through the fossil, and curve more 

 or less downward on all sides towards it. No roots could 

 be observed attached to this tree; yet from its position 

 at right angles to the strata, and the peculiarity of the strati- 

 fication, I think it stands on the spot where it originally grew. 

 Indeed, there seems to me little doubt that most of the coal 

 seams, even in north Northumberland, have been formed of 

 plants and trees which grew, during the Carboniferous Era, in 

 the district now occupied by the coal beds. The under clay 

 usually beneath each coal seam was the surface soil, on which 

 the plants and trees grew ; and it is now found more or less 

 traversed by the Stigmaria Jicoides, which was the root of 

 the Sigillaria, the trunks of which have largely contributed 

 to the formation of the coal. As this fossil tree is frequently 

 to be seen in Northumberland, it may add to the interest of 

 these notes to give the following description from my Fossil 

 Flora of the Eastern Borders. " The structure of the Sigil- 

 lariae differs widely from that of any living plant ; it is, how- 

 ever, essentially acrogenous; and the nearest analogue to 

 these majestic trees of other times is the Lycopod or lowly 

 creeping club moss ; yet the radial arrangement of the woody 

 tissue and the presence of medullary rays and a sheath, bring 

 them into a distant relationship to exogenous vegetation. 

 Brongniart considers them allied both to the Lycopod and to 

 the Cycas ; they form, therefore, a connecting link between 

 orders, which stand far apart in existing nature. Composed 



