292 



STIGMARIA. 



they showed Stigmaria-scars, and on many of them no surfaces of fracture 

 could be seen. For this reason Goppert pronounced these nodules to be 

 young individuals, perfectly preserved all round, which would branch by 

 further bifurcation of their extremities and develope into the well-known 

 rhizomes. He supposed the tuber-like stock to have been formed by 

 irregular swelling at some spot in its middle portion, and that it might under 

 favourable circumstances grow into a Sigillaria-stem, or in other cases 

 continue for a very long time or even always in its original condition. For 

 the mode of development of this tuber-like stock he appeals to an observa- 

 tion of Stcinhauer l , who saw several branches of Stigmaria proceed from a 

 central tuber from one to four decimetres thick, and reach a length of 

 twenty decimetres. And he himself on th same journey in Westphalia 

 observed a similar specimen on a perpendicular wall of Carboniferous 

 sandstone at Kirchhorde near Dortmund, varying from fifty to a hundred 

 feet in height, and has given a figure of it 2 . It was a tuber-like body of 

 irregular form some two feet thick, having branches of Stigmaria going off 

 from it in every direction, the figure gives four of them, but with their 

 extremities not preserved or hidden in the stone. The account has no 

 doubt an air of truth about it, and explains satisfactorily that which it had 

 to explain ; and recent vegetation supplies analogous cases for comparison, 

 as in Psilotum and less exactly in Corallorhiza, Epipogium and other plants. 

 This is why it has so greatly influenced the accounts given by all subse- 

 quent authors, but the foundation on which it rests is not really of much 

 value, for the tuber-like bodies from Bochum from Goppert's collection, for 

 some of which I am indebted to F. Romer, are in fact shapeless objects in 

 part slicken-sided, and can prove nothing. 



While Goppert supposes all Stigmariacto spread like spokes of a wheel 

 from a central stock or from the base of Sigillariae, and to elongate in every 

 direction with repeated bifurcations, the French authors Renault 3 and 

 Saporta and Marion 4 are of a somewhat different opinion on this point. 

 The first says, for example 5 : ' The life of a Stigmaria was undoubtedly 

 confined for a long time to the almost unlimited production of dichotomous 

 ramifications.' But then single peripheral extremities of branches of these 

 rhizomes are supposed to become erect and as ' aerial buds ' to give rise to 

 the stems, which in their turn put forth two proper roots (' stigmarhizes ') 

 at their base. Hence the four diverging and repeatedly bifurcating branches 

 of the base of the stem must be 'stigmarhizes,' and somewhere between 

 them must be the place where the rhizome-shoot was broken off, the apex 

 of which grew upwards in the form of a stem. Putting aside the purely 

 hypothetical nature of these ' stigmarhizes,' the facts do not give the smallest 



1 Steinhauer (1). 2 Goppert (3), t. 35. 8 Renault (2), vol. i, p. 162. 4 Saporta et 



Marion (2), p. 55. * Renault (2), vol. i, p. 163. 



