[24] See the important memoir of Barrande on the Silurian Brachiopods, in which, as the result of the most elaborate and detailed comparisons, he concludes that in the case of these shells, as in that of the Cephalopods and Trilobites, the introduction of species in geological time has not occurred by modification, but must have depended on a creative process. It is such painstaking researches as those of the great Bohemian palæontologist which must finally settle these questions, in so far as geology is concerned.
[25] Geological Magazine, November, 1869.
[26] The genus Buthotrephis includes supposed branching sea-weeds of the Silurian. For this reason I would propose the name Protannularia for these plants.
[27] Lycopodiaceæ.
[28] Allied to those named by Brongniart Aetheotesta.
[29] Cordaites.
[30] Paper by Sir W. Dawson in Chicago Academy’s Bulletin, 1886.
[31] Calamodendron and Arthropitys are forms of this kind.
[32] Grand’ Eury and Williamson have directed attention to this in the case of those of France and England.
[33] Amphioxus.