. Studies in fossil botany . Paleobotany. LEPIDOSTROBUS **« 187 spores of Lepidostrobus and allied fructifications are very abundant in the Carboniferous formation, and show a great variety in size and surface-sculpture. Some of these megaspores (which were investigated by Messrs. Kidston and Bennie) appear to be identical with those of Lepidostrobus Veltheimianus; in addition to the spines, these detached specimens show a curious three- lobed appendage to the membrane of the spore (see Fig. 75, D), which very commonly appears in the sections also. It is probable that this structure, which was
. Studies in fossil botany . Paleobotany. LEPIDOSTROBUS **« 187 spores of Lepidostrobus and allied fructifications are very abundant in the Carboniferous formation, and show a great variety in size and surface-sculpture. Some of these megaspores (which were investigated by Messrs. Kidston and Bennie) appear to be identical with those of Lepidostrobus Veltheimianus; in addition to the spines, these detached specimens show a curious three- lobed appendage to the membrane of the spore (see Fig. 75, D), which very commonly appears in the sections also. It is probable that this structure, which was of very general occurrence in the megaspores of Lepido- dendreae, formed a passage for the admission of the microspores or of the spermatozoids pro- duced by them. Microspores are often found entangled among .... r , Fig. 76.—Lepidostrobusfoliaceus. the bristles of the megaspores. Megaspore (somewhat coi- The megaspores of Lepidos- S^^S trobus foliaceus, a Coal-measure 5,™,", New PWokgist. s. J Coll. 1217. species, of which until recently only the microsporangia were known, appear to have numbered not more than four in each sporangium, and possess a curious episporic appendage, comparable to the so-called " swimming apparatus" of Azollal (see Fig. 76). In favourable cases the prothallus is preserved within the megaspore. This is sometimes the case in L. Veltheimianus, as is well shown in Fig. yj ; the prothallus is here almost complete, and fills the megaspore. Fig. 78, from a photograph, represents 1 R. Scott, New Phytologist, June 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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