. Actes du IIIme Congrès international de botanique, pub. au nom de la commission d'organisation du Congrès. Botany. 282 the roots, ail indicate an affinity witli Cycadopliyta. Broadly speaking, thèse results hold good for the Medulloseae generally. though in the more elaborate Perraian species the differentiation of the stèles among themselves, and certain peculiarities of the secondary growth niay render the likeness to Cycadean stems more striking. On thèse anatomical grounds the Medulloseae were included by Potonié in 1897, in his happily named intermediate group Cycadofilices. Tiie point
. Actes du IIIme Congrès international de botanique, pub. au nom de la commission d'organisation du Congrès. Botany. 282 the roots, ail indicate an affinity witli Cycadopliyta. Broadly speaking, thèse results hold good for the Medulloseae generally. though in the more elaborate Perraian species the differentiation of the stèles among themselves, and certain peculiarities of the secondary growth niay render the likeness to Cycadean stems more striking. On thèse anatomical grounds the Medulloseae were included by Potonié in 1897, in his happily named intermediate group Cycadofilices. Tiie point on which the question of the systematic position of the family turned, was clearly that of the nature of the fructification. It had been suggested, some years ago, on grounds of association and of common structural features, that seeds of the genus Trigonocarpon might probably prove to belong to species of Ale- thopteris or Neurop- teris (WiLD 1900). But this reniained nothing more than a probable suggestion, and . it was not till the close of 1903 that \ve received, from my friend Mr. Kidston, the first definite proof that a meniber of the Neuropterideae was a seedbearing plant. Mr. Kidston showed that certain large seeds, resembling a hazel-nut in size and form, from the Coal-Measures of Dudley in England, were borne on portions of a rachis to which the characteristic pinnules of the well known species, Neuropteris heterophylla, were still attached (Figs. 4 and 5). The seeds hâve a fibrous envelope, and are placed by their discoverer in the genus Rhabdocarpus of Goeppert and Berger (Kidston, 1904). They are, however, of the radiospermic type, and must not be confounded with the platyspermic seeds, which, following Brongniart, we more usually associate with the generic name Rhabdocarpus. Mr. Ividston's discovery thus proved that Neuropteris heterophylla was a seed-bearing plant, and that the seeds were borne on a frond, differing but little, so far as one can judge by t
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