. Fossil plants : for students of botany and geology . Paleobotany. xx] RECENT FERNS 303 the form of finely divided leaves identified by earlier collectors as those of a parasitic Trichomanes (fig. 235). In a letter written by W. H. Harvey in 1837 accompanying the specimen shown in fig. 235, he says, " Apropos of Hemitelia, be it known abroad that supposed parasitical .is not a parasite, but a part of the frond of ; The delicate reduced pinnae remain on the stem and form a cluster at the base of the fronds ^. In many species the sporophylls are distinguished f
. Fossil plants : for students of botany and geology . Paleobotany. xx] RECENT FERNS 303 the form of finely divided leaves identified by earlier collectors as those of a parasitic Trichomanes (fig. 235). In a letter written by W. H. Harvey in 1837 accompanying the specimen shown in fig. 235, he says, " Apropos of Hemitelia, be it known abroad that supposed parasitical .is not a parasite, but a part of the frond of ; The delicate reduced pinnae remain on the stem and form a cluster at the base of the fronds ^. In many species the sporophylls are distinguished from the. Fig. 234. Polypodium quercifolium. (Much reduced: M, Mantle-leaves.) sterile fronds by segments with little or no chlorophyllous tissue, as in Onodea struthiopteris^ in which, each year, the plant pro- duces a funnel-shaped group of sterile leaves followed later in the season by a cluster of sporophylls; or, as in many other genera, the fertile leaves are distinguished also by longer petioles and thus serve as more efficient agents of spore-dissemination. In Ceratopteris the narrow segments of the taller fertile leaves ' A striking example of these so-called Aphlebiae of Hemitelia may be seen at the Royal Gardens, Kew. 2 Luerssen, in Babenhorst (89) A. p. 483, fig. 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 Seward, A. C. (Albert Charles), 1863-1941. Cambridge : University Press
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
