. The testimony of the rocks; . CONE. longed to any coniferous tree. In one of these (Fig. 138),the ligneous bracts or scales, narrow and long, and grad-ually tapering till they assume nearly the awl-shaped form,cluster out thick from the base and middle portions of thecone, and, like the involucral appendages of the hazel-nut,or the sepals of the yet unfolded rose-bud, sweep gracefullyupwards to the top, where they present at their marginsminute denticulations. In another species the bracts arebroader, thinner, and more leaf-like: they rise, too, morefrom the base of the cone, and less from i
. The testimony of the rocks; . CONE. longed to any coniferous tree. In one of these (Fig. 138),the ligneous bracts or scales, narrow and long, and grad-ually tapering till they assume nearly the awl-shaped form,cluster out thick from the base and middle portions of thecone, and, like the involucral appendages of the hazel-nut,or the sepals of the yet unfolded rose-bud, sweep gracefullyupwards to the top, where they present at their marginsminute denticulations. In another species the bracts arebroader, thinner, and more leaf-like: they rise, too, morefrom the base of the cone, and less from its middle por-tions ; so that the whole must have resembled an enormousbud, with strong woody scales, some of which extended 4:84 ON THE LESS KNOWN from base to apex. The first described of these two spe-cies seems to have been more decidedly a cone than theother; but it is probable that they were both constating Fiff. links between such leathern seed-bearing flowers as we finddeveloped in Cycas revoluta^ and such seed-bearing conesas we find exemplified in Zamia pungens. Tlie bud-likecone, however, does not seem to have been that of a Cyca-daceous plant, as it occupied evidently not a terminal posi-tion on the plant that bore it, like the cones of Zamia orthe flowers of Cycas, but a lateral one, like the lateralflowers of some of the Cactus tribe. Another class ofvegetable forms, of occasional occurrence in the Helmsdalebeds, seems intermediate between the Cycadacese and theferns: at least, so near is the approach to the ordinaryfern outline, while retaining the stifl ligneous character of2amia, that it is scarce less diflicult to determine to which FOSSIL FLORAS OF SCOTLxVND. 485 Fig. 140.
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