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Walter Leinfellner 《Plant Systematics and Evolution》1970,118(1-2):108-120
Zusammenfassung Wie erwartet, gleichen die Karpelle der Caesalpiniaceen und Mimosaceen in ihrem Bau weitgehend jenen der Papilionaceen. Neben epeltaten Karpellen, die in überwiegender Zahl auftreten, werden häufig auch peltate gefunden, deren Schlauchteil jedoch meist vom auslaufenden Ventralspalt geschlitzt wird. Mehrkarpellige Gynözeen wurden vonCassia montana, wo abnormerweise ein oder zwei rudimentäre Karpelle zusätzlich ausgebildet werden, und vonAffonsea juglandifolia untersucht. Die freien Karpelle des normal mehrkarpelligen Gynözeums der letzteren Art sind modifiziert peltat gebaut, da ihr niedriger Schlauchabschnitt mit einem oberflächlichen Ventralschlitz versehen ist. 相似文献
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Prof. Dr. Lothar Geitler 《Plant Systematics and Evolution》1973,122(3):185-194
Summary The correlation between the start of chromatophore division and cell division is very different in various species ofEunotia. In some species the chromatophore division occurs before, in others after cell division.
Eunotia pectinalis var.polyplastidica, with eight chromatophores per cell, represents an extreme type of behaviour in so far as two of the four plastids in each daughter cell prior to their division are shifted to the new hypovalve while the other two rest in situ. There occur two patterns of distribution of the four plastids, and that in the ratio 11, whereas the theoretically possible third pattern is never realized. The cause of that phenomenon is discussed. The division of the four plastids, in the meantime grown to full size, is performed not before they have reached their definitive equilibrium position at the epivalve or, respectively, at the hypovalve in twos. InEunotia pectinalis var.polyplastidica, by its mode of chromatophore division, the constant dissymmetric (right-left-handed) arrangement of the growing chromatophores, established inEunotia arcus, is not to be expected and is in fact not realized. InEunotia lunaris, however, the shift of the daughter chromatophores, in relation to the dorsiventrality of the cell, shows not only the same kind of dissymmetry as inEunotia arcus but also the same direction of shifting.The four and four chromatophores inEunotia pectinalis var.polyplastidica correspond to the two chromatophore plates in other species but the are not comparable with the numerous little chromatophore discs of Diatomaceae and other species the number of which decreases with the reduction of cell size.Cells ofEunotia pectinalis var.polyplastidica are capable to move by raphe action.
Herrn Dr.Franz Berger zum 70. Geburtstag gewidmet. 相似文献
Herrn Dr.Franz Berger zum 70. Geburtstag gewidmet. 相似文献
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Prof. Dr. H. Berg 《International journal of biometeorology》1958,2(1):41-54
Ohne Zusammenfassung 相似文献
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Zusammenfassung AlsGloeochrysis apyrenigera wird eine neue kaltstenotherme Chrysophycee beschrieben. — Der Chromatophor vonPhaeodermatium ist seitenständig und zeigt die auch für andere Chrysophyceen typische mittlere, beidseitige Einschnürung, die keine Teilungsstruktur ist. 相似文献
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Hans-Peter Schultze 《Pal?ontologische Zeitschrift》1981,55(1-2):71-86
Hennig’s principle of analysis of characters is the best available method at present to analyse the relationship within one group or between groups. The analysis of characters has to be separated clearly from their phylogenetic and classificatory interpretation. New terms have been proposed to distinguish the status of classification of groups (synapogen, symplesiogen, paragen) from the character analysis (synapomorph etc.) and from its phylogenetic development (monophyletic, paraphyletic, polyphyletic). The origin of tetrapods is used as an example to show that every scheme of relationship depends on the use and evaluation of characters, the accepted homologies. A stabile classification is thus an illusion. No absolute criterion exists to recognize homologies. 相似文献