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| Sen, U.; Hennipman, E.. |
| The stomata as occurring on the fronds of the sporophytes of a large number of Polypodiaceae s.s. (Filicales) are investigated. A number of different stomatal types is recognised, (newly) described, and their ontogeny investigated. The different types of stomata are discussed in relation to their possible significance for tracing phylogenetic relationships in the Polypodiaceae following a cladistic analysis. |
| Tipo: Article / Letter to the editor |
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| Ano: 1981 |
URL: http://www.repository.naturalis.nl/record/525406 |
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| Sen, U.; De, B.. |
| On the basis of ontogeny and arrangement of the surrounding cells the stomata in ferns are classified into twenty-four types of which seven – plupolocytic, pseudocopolocytic, sepcopolocytic, pseudohemiparacytic, pluhemiparacytic, pluparacytic and codiacytic – are new. The ontogenetic interrelationships among different stomatal types are traced and the role of stomata in determining the taxonomic position of Psilotum, Tmesipteris and the Ophioglossum group of genera are discussed. It is concluded that the mesogenous and mesoperigenous types of stomata are not distinct entities – one is the derived form of the other. The polocytic stoma which is mesoperigenous in origin is, however, not accepted as the direct descendant of the anomocytic (perigenous) type. |
| Tipo: Article / Letter to the editor |
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| Ano: 1992 |
URL: http://www.repository.naturalis.nl/record/524430 |
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| Holttum, R.E.; Sen, U.; Mittra, D.. |
| In the first paper of this series (Holttum, 1969) I gave a brief summary of taxonomic treatment of the family Thelypteridaceae in the present century, and stated that in my judgement no satisfactory subdivision of the family, as represented in the tropics of the Old World, had yet been achieved, the arrangements of Ching (1963) and Iwatsuki (1964) being in part inadequate because the authors were not sufficiently acquainted with the majority of species in the Malayan region and in the Pacific, which far outnumber those of mainland Asia. I have been attempting a complete survey of all species of Asia, Malesia, and the Pacific, and it has become evident to me that a study of a wider range of characters than those used in most taxonomic species-descriptions... |
| Tipo: Article / Letter to the editor |
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| Ano: 1970 |
URL: http://www.repository.naturalis.nl/record/524647 |
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