. Studies in fossil botany . Paleobotany. MACROSTACHYA 73 and these cones are among the most striking fossils of the Coal-period. There is great doubt as to the internal structure of the cones. M. Renault examined the carbonised cones of a Macrostachya, found in con- nection with the stem, which was of the Calamitina type (see below, p. 74), and showed the usual Cala- mitean structure. The fructification proved to be heterosporous, the microsporangia and megasporangia occurring on the same strobilus, as is the case in Calamostachys Casheana} 7. Classification.âBefore leaving the Calamarieae I
. Studies in fossil botany . Paleobotany. MACROSTACHYA 73 and these cones are among the most striking fossils of the Coal-period. There is great doubt as to the internal structure of the cones. M. Renault examined the carbonised cones of a Macrostachya, found in con- nection with the stem, which was of the Calamitina type (see below, p. 74), and showed the usual Cala- mitean structure. The fructification proved to be heterosporous, the microsporangia and megasporangia occurring on the same strobilus, as is the case in Calamostachys Casheana} 7. Classification.âBefore leaving the Calamarieae I must say a few words as to their classification. This is a most difficult, and indeed in the present state of our knowledge, in- soluble question, because we only have the plants as preserved in the form of fragments. Consequently, we shall not be surprised to find that Fig. 32.âMacrostachya. in- the classification of Calamarieae has /undn>uii/ormis. Cone 1 1 . Hi. rr â borne laterally on a been based on totally different pnn- branch. Hair nat. size. ciples, according to the parts of the After Weiss' plants selected. For example, Weiss classified Cala- marieae by means of the characters presented by their medullary casts, and more especially according to the form and distribution of the scars marking the position of the branches. For the purposes of geologists his is 1 Notice sur les Calamarties, Part iii., Autun, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Scott, Dukinfield Henry, 1854-1934. London, A. and C. Black
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