XVIl] STIGMARIA 233 



1845, 1846 and 1849 ; in the last paper he figured a specimen, 

 which has become famous, showing a Syringodendron stem 

 terminating in branching Stigmarian (or possibly Stigmariopsis) 

 roots bearing on the lower surface a series of what he called 

 conical tap roots^ A similar specimen discovered in Central 

 France nearly fifty years later demonstrated the accuracy of 

 Brown's description. 



Despite these discoveries the root-like nature of Stigmaria 

 was not universally accepted. It was, however, generally agreed 

 that Stigmaria formed the roots of Sigillaria ; it was, moreover, 

 held by some that Lepidodendron stems also possessed this 

 type of root, an opinion based on Brown's record and on the 

 occurrence of Stigmaria in beds containing Lepidodendron but 

 no Sigillaria stems, as in the volcanic beds of Arran and else- 

 where, and on observations of Geinitz and others^. There is 

 now general agreement that Lepidodendron and Sigillaria had 

 the same type of "root," though the connexion of Stigmaria 

 with the former was not so readily admitted, and indeed the 

 evidence in support of it is still very meagre. Goeppert and 

 other authors were unable to believe that the numerous species 

 of Sigillaria possessed roots of so uniform a type, but Goeppert, 

 by his recognition of several varieties of Stigmaria, supplied 

 a partial answer to this objection. 



Messrs Mellor and Leslie' have described and figured some 

 large casts of roots exposed in Perino-Carboniferous rocks in 

 the bed of the Vaal river at Vereeniging (Transvaal) which 

 exhibit certain features suggesting comparison with Stigmaria. 

 Some of these reach a length of 40 — 50 feet and, when 

 complete, were probably not less than 100 feet long: in some 

 of them the centre of the cast from which forked arms spread 

 almost horizontally shows a depression in the form of a cross 

 indicating a regular dichotomous branching like that of Stig- 

 maria. The authors incline to the belief that the roots belong 

 to Noeggerathiopsis and not to a lycopodiaceous plant, though 

 Lepidodendroid stems are abundant in the sandstone a few feet 



1 Brown (49). This figure is reproduced by Williamson (87) A. p. 16. 



2 Williamson (87) A. p. 3. Solms-Laubaoh (91) A. p. 284. 

 ^ Mellor and Leslie (06). 



