. Fossil plants : for students of botany and geology . Paleobotany. 408 BENNETTITALES [CH. of lociJi are bounded by flattened cells and there are 10—20 loculi in each of the two rows: de- hiscence of the individual locuh occurs in the middle of the inner wall. f^ Cycadeoidea Marshiana Ward. This Lower Cretaceous Black Hills species^ affords an admirable example of a method of branching exhibited by some stems: as shown in Wieland's photographs^ there may be five or six large and massive trunks all in the same stage of fructification, differing but Httle in size and forming a cluster resembhng
. Fossil plants : for students of botany and geology . Paleobotany. 408 BENNETTITALES [CH. of lociJi are bounded by flattened cells and there are 10—20 loculi in each of the two rows: de- hiscence of the individual locuh occurs in the middle of the inner wall. f^ Cycadeoidea Marshiana Ward. This Lower Cretaceous Black Hills species^ affords an admirable example of a method of branching exhibited by some stems: as shown in Wieland's photographs^ there may be five or six large and massive trunks all in the same stage of fructification, differing but Httle in size and forming a cluster resembhng independent plants growing in close proximity to one another. There is apparently no central or major axis and the habit is therefore very different from that of a branching Byicldandia. Cycadeoidea Marshiana bore large ovulate pyxiform strobih projecting slightly beyond the leaf- bases; they are 5 cm. long with a maximum diameter of 3-5 cm. and have an elongated receptacle bearing short scales and sporophylls. The apical bud of one of the trunks shows particularly well in transverse section the dense ramental packing between the bud-scales*. Similar clusters of short and thick trunks occur in Cycadeoidea swperha and other American species. In the small bisporangiate flowers of this species* the micro- sporophyUs, 11 or 12 in the verticil, are characterised by the presence of a ventral furrow which, as Wieland suggests, may be comparable on a much simpler scale with the winged sporophylls of Cycadeoidea colossalis (fig. 533). The disc splits up at a distance. Cycadeoideadacotensis. Synangium in longitudinal section showing the thick pedicel, the line of dehiscence, and two locuU with a few microspores. (After Wieland; X 40.) 1 Ward (98) p. 208. » Ibid. PI. XTX. fig. 5. ' Wieland (06) Pis. vn.—^ix., xn., xni. * Ibid, passim; (12).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration
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