. Maryland geological survey. chen Cycadophyten, Handl., Band xxxvi, No. 4, 1902. ^ Carruthers, Trans. Linn. Soc. Lond., 1870, vol. xxvi, pp. 675-708, pi. liv-lxlii. ^ Solms-Laubacli, Ann. of Botany, 1891, vol. v, pp. 419-454, pis. xxv, xxvi. * Lignier, Veget. Foss. de Normandie, Caen, 1894. »Nathorst, Kgl. Svenska Vetens-Akad. Handl., Band xlv, No. 4, 1909, lUd.,Band xlvi. No. 4, 1911. Wieland, loc. cit. Maryland Geological Survey 317 seed plants, and the cycads still further emphasize this resemblance toferns in their mode of fertilization, i. e., by means of ciliat
. Maryland geological survey. chen Cycadophyten, Handl., Band xxxvi, No. 4, 1902. ^ Carruthers, Trans. Linn. Soc. Lond., 1870, vol. xxvi, pp. 675-708, pi. liv-lxlii. ^ Solms-Laubacli, Ann. of Botany, 1891, vol. v, pp. 419-454, pis. xxv, xxvi. * Lignier, Veget. Foss. de Normandie, Caen, 1894. »Nathorst, Kgl. Svenska Vetens-Akad. Handl., Band xlv, No. 4, 1909, lUd.,Band xlvi. No. 4, 1911. Wieland, loc. cit. Maryland Geological Survey 317 seed plants, and the cycads still further emphasize this resemblance toferns in their mode of fertilization, i. e., by means of ciliated motilesperms. When we come to consider the method and organs of fructification ofthe Mesozoic Bennettitales (so called), instead of finding them of asimpler type, as we might expect, we find a much greater complexity,while on the other hand the vegetative structures are simpler than isthe case in the existing cycads. The fructifications in the former asexemplified in the genus Cycadeoidea are long axillary bodies inserted. Fig. 7.—Restoration of an unexpanded bisporangiate strobilus with someof bracts removed, about one-half natural size. (After Wieland.) in large numbers among the crowded leaf bases (see Cycadeoidea mary-landica). About half their length is taken up by the peduncle or stalkon which spirally arranged bracts are borne, and these completely investthe essential organs (see fig. 7). Distad, this peduncle expands into areceptacle from the rim of which springs a whorl of staminate, com-pound, fern-like sporophylls on which the pollen is produced, not insimple anthers, but in compound pollen-sacs comparable with the synangiaof the marattiaceous ferns. These Cycadeoidea stamens in their habitsuggest a comparison with the ovulate fructification named by Renault 318 Systematic Paleontology Cycadospadix milleryensis from the Permian of Autun, Prance/ Theseed-bearing sporophylls of Eenaults interpretation would then bemorphologically the fertile leaflets of a single
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