6id Contributions towards Establishing the General Character 



manifest from the fact, that, up to the present time — although I have 

 now examined several specimens — I have not fallen in with one which 

 exhibits the upper surface otherwise than truncated : further, when the 

 centre of a Stigmaria has fallen from the roof, a portion in the shape of 

 a stem, and answering to the truncated surface, is often seen remaining 

 in the roof, and passing upwards.* 



The disposal of these two points (and they have, I am decidedly of 

 opinion, been the greatest hinderances to the working out of the true 

 character of this fossil) , not only proves, that the prevailing opinion re- 

 garding the form of Stigmaria is erroneous, but it leads to the inference, 

 that what has hitherto been looked upon as the centre of this fossil, is in 

 the form of a root stock deprived of its stem. 



All the specimens of Stigmaria which have been seen in a perfect 

 condition, or nearly so, have their branches running out in the manner 

 of wide- spreading roots : this will be sufficiently evident by consulting 

 figure 1, plate 31, of the " Fossil Flora." Besides the specimen just 

 referred to, several others are still to be seen fixed in the roofs of several 

 pits in this district. At Felling, a very large specimen occupies the roof 

 of one of the galleries : it is impossible to ascertain its size, as it passes 

 into an un worked part of the mine : some of the branches, at a little dis- 

 tance from their commencement, measure eighteen inches across in the 

 compressed state. An idea may be formed of the dimensions which some 

 Stigmarias attain, from the statement communicated to me by the head 

 wasteman of Felling pit, that he has traced the impression of a single 

 branch for full fifty feet, without finding its terminations. I am quite 

 disposed to credit this statement, for I myself have measured an im- 

 pression of this fossil in the roof of Jarrow pit, and succeeded in fol- 

 lowing it for thirty feet, until it disappeared in a part where the work- 

 men had not carried on their operations. And, very lately, I have 

 obtained for the Newcastle Museum, portions of three different speci- 

 mens, equally confirmatory of the immense size which some Stigma- 

 rias attain. The first is a branch fifteen feet in length, rather flexuose, 

 and remarkably uniform in thickness, which is four inches. The 

 second differs from the last in being singularly yet gracefully tor- 

 tuous, and in diminishing at one end to a mere film ; the opposite end 

 appears to have been joined to the main body of the fossil ; or, what is 

 more probable, this specimen may have been one of the off- sets of a 

 divided branch ; it is eleven feet long, and five inches in thickness, at 

 the largest end. The third consists of three furcated branches, which 

 have been broken off from the central stock ; the two off- sets of one of 

 these furcated branches are respectively seven and two feet long, and 



♦ In general, these perpendicular stems are so polished or slickensided, that it 

 is impossible to identify them with any known fossil r and nothing is more common 

 than to see the surface of a so-called centre of Stigmaria as smooth as glass. The 

 last is called a " kettle bottom" by the miners. I would suggest that this pheno- 

 menon has been produced by the fossil offering some resistance-.to thp enormous 

 compression into which the sarroundingg rock has been subjected. 



