NORTH STAFFORDSHIRE COAL FOSSILS. 195 



These were standing upright, and no doubt upon the 

 exact spot on which they grew. 



Sigillaria was one of the largest of the ancient 

 carboniferous trees, and helped in no small degree in the 

 formation of coal. In the specimens above mentioned, 

 the original structure of the interior of the tree was not 

 preserved. It appears to have decayed, and as hollow 

 trunks they would long stand exposed to the fury of the 

 elements. The interior was filled with ferns, calamites, 

 lepidostrobus, and other vegetable remains, which must 

 have been washed or fallen in while they stood hollow. 

 Around the base of the trunks numerous ferns and other 

 plants were found, testifying to the luxuriance of the 

 vegetation of that period. 



Stigmaria is one of the commonest of our coal plants. 

 Fine specimens are found in the Bassy-mine ironstone. 

 It is common in all our plant-bearing beds, especially in 

 the fire-clays which underlie the different seams of coal. 



Perhaps no class of fossil plants occurs in such a 

 beautiful state of preservation as the Ferns, many species 

 of which are abundant. Upwards of 140 species have 

 been recorded from British carboniferous rocks, of which 

 number about forty species have been found in this coal- 

 field. In the Knowles rock, Moss coal rock, Peacock 

 marl, and in a bed of marl near the Yard coal, many 

 fine specimens have been found. Mr. Lunn has collected 

 a fine series from a bed of grey rock which was passed 

 through during the cutting of the railway at Scott Hay, 

 near Silverdale. Specimens in a good state of preservation 

 have been collected at Adderley Green, Longton, and 

 at Feuton. Good specimens of plants are not rare in the 



