CONTROVERSIAL PERIOD 255 



Lycopsida and Pteropsida of Prof. Jeffrey, though the suggested 

 relation to the higher plants would not be accepted by any 

 modern botanist. In spite of Williamson's tactical error in 

 weighting himself with a doubtful scheme of classification, and 

 in spite also of a faulty terminology, it is easy to see now that 

 he had the best of the controversy, for he knew the facts about 

 the structure of the Carboniferous Cryptogams, which his oppo- 

 nents, at that time, did not. They stuck to generalities, and 

 those who take the trouble to rake the ashes of this dead 

 controversy will at least learn that dogmatism is not confined 

 to theology! 



An interesting point is that Williamson at that time spoke of 

 Brongniart almost as an ally\ The conviction that the old 

 Lepidodendrons and Calamites were "exogenous" then seemed 

 to him of greater importance even than his belief that they 

 were Cryptogams. The English opposition, however, was never 

 really formidable, and so a change of front became necessary, to 

 meet the attacks of the powerful French school. Williamson 

 was an energetic disputant ; not content with his numerous 

 English publications, he published, in 1882, an article in the 

 Annates des Sciences Natiirelles, entitled "Les Sigillaires et les 

 Lepidodendrees." This was translated into French for him 

 by his colleague Marcus Hartog, whose assistance he greatly 

 valued. He describes this vigorous polemical treatise as "flung 

 like a bombshell among my opponents." 



In time they came over, one by one, to his views, and even 

 the most redoubtable of the French champions Bernard, Renault, 

 before the close of his life, had made very considerable conces- 

 sions to Williamson's side of the question. There is no need 

 to dwell on the controversy ; every student now knows that the 

 Club-mosses, the Horse-tails and the Sphenophylls of Palaeozoic 

 times formed abundant secondary tissues homologous with those 

 of a Gymnosperm or a Dicotyledon; the case of the Spheno- 

 phylls shows that the character was not limited to arborescent 

 plants then any more than it is among Dicotyledons at the 

 present day. At the same time, as Williamson maintained, 

 these groups of plants were, broadly speaking, cryptogamic. 



^ Loc. cit., p. 409. 



