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1.
Cynoglossopsis somaliensis H. Riedl, sp. nov., is described as a new species of the hitherto monotypic genusCynoglossopsis Brand which is closest related toCynoglossum L. but has to be included inBoraginoideae-Eritrichieae from the way the nutlets are attached to the gynobasis.
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2.
Within agaric fungi whorled (multiple) clamps have been described so far only for the homothallicCoprinus myceliocephalus Lange. The new speciesCoprinus verticillatus Schulz-Weddigen (ined.) develops fertile mycelia which form septae without or with 1–5 clamps. Stronger hyphae tend to branch dichotomously. Most cells of the vegetative system contain many nuclei. Though single spore cultures remain sterile, they can develop multiple clamps, too. Moreover, very young mycelia produce a special type of oidiophores. According to its mating interactions a bipolar pattern characterizes the heterothallicC. verticillatus.
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3.
Viscin threads and other pollen connecting threads of some angiosperm families were investigated, especially those ofEricaceae. According to the definition adopted, viscin threads are ± long exinous processes which consist of exinous material and connect pollen grains or tetrads. Such viscin threads are found within theOnagraceae, Caesalpiniaceae, Ericaceae, andMimosaceae only. While they differ in structure and composition, they always consist of sporopollenin and exhibit a very strong stickiness, even after all viscid substances have been removed by acetolysis. In contrast, the pollen connecting scleroprotein threads ofOrchidaceae and the cellular threads ofStrelitzia reginae Aiton. (Musaceae) are not connected with the exine surface, are destroyed by acetolysis, and thus do not correspond to viscin threads.
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4.
Cellulomonas cartalyticum was found to contain a peptidoglycan type different from that of the other species ofCellulomonas. The diamino acid is lysine instead of ornithine and the interpeptide bridge consists ofd-Asp-d-Ser. The same peptidoglycan type occurs inCorynebacterium manihot, Brevibacterium liticum andArthrobacter luteus. These non cellulolytic organisms are most likely not closely related withCellulomonas cartalyticum, as indicated by the very different G+C content of their DNA, although they formed a narrow cluster includingC. cartalyticum when numeric taxonomical methods were applied.
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5.
The new familyStephanosporaceae (Basidiomycetes, Fungi) is proposed. As far as known, the range of the family covers aphyllophoroid (Lindtneria) and gastroid genera (Stephanospora) which are characterized by strongly sculptured and coloured spores. From the micro- and ultrastructural point of viewLindtneria andStephanospora are practically undistinguishable. Therefore, the two genera are considered to be closely related, despite their striking differences concerning the macromorphology of their carpophores.
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6.
Different members of the Angiosperm familiesOleaceae, Scrophulariaceae, Plantaginaceae andAsteraceae with variable modes of pollination were studied in relation to ultrastructure of pollenkitt and exine. In entomophilous representatives the mostly electron-dense and homogeneous pollenkitt is located on the outside layer of the exine, making the pollen sticky. In related anemophilous taxa the pollenkitt mostly is electrontransparent and inhomogeneous; it becomes inactive by remaining in the loculus or sinking to the bottom of the exine caves; this makes the pollen powdery. According to such criteria,Fraxinus ornus andRhinanthus serotinus are entomophilous, whileFraxinus excelsior is anemophilous. The pollen ofLathraea squamaria eventually becomes powdery and suited for wind dispersal. The broad transition field between entomo- and anemophily is demonstrated byPlantago andArtemisia. Plantago lanceolata is anemophilous, whilePl. serpentina andPl. media are amphiphilous.Artemisia nitida andA. mutellina are entomophilous,A. absinthium, A. pedemontana andA. gabriellae are amphiphilous, but tend towards entomo- (A. absinthium) or anemophily (A. gabriellae), whileA. chamaemelifolia and especiallyA. vulgaris are anemophilous.
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7.
None of the 27 studiedRhinanthoideae is host-specific. Some host plants are preferred (e.g.Rosaceae, Fabaceae, Lamiaceae, Asteraceae, Cyperaceae, andPoaceae), others are strictly avoided (e.g.Orchidaceae). Self-parasitism and parasitism on rhizomes are wide-spread. This and the number of haustoria developed are closely related to number of host plants available. Most of theRhinanthoideae studied have haustoria also at the main root. No serious injury of host plants byRhinanthoideae under natural conditions can be demonstrated.
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8.
Detailed analyses of karyology and leaf morphology do not support relationships betweenFlacourtiaceae andTiliaceae. In spite of different chromosome numbers,Prockia (2n = 18),Flacourtia (2n = 22) andRawsonia (2n = 22) are very similar in karyomorphology, indicating a certain karyological uniformity withinFlacourtiaceae. Lacistema (2n = ca. 62) appears more isolated. On the other hand, theTiliaceae Grewia (2n = 18) andLuhea (2n = 36) have much in common and differ remarkably from the Flacourtiaceous genera. The salicoid leaf-teeth ofProckia are also found inIdesia, but never inTiliaceae. Epidermis ultrastructure reveals certain relationships betweenProckia andFlacourtia in contrast to the strongly differingGrewia. Idesia has a rare und unique epidermis sculpture. — Basic chromosome numbers and chromosomal evolution within theFlacourtiaceae are discussed.
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9.
The pollenkitt ofTilia platyphyllos andT. tomentosa is produced during the tetrade-stage by the tapetum plastides. After tapetum degeneration pollenkitt and accompanying substances are deposited predominantly in the intrabacular spaces of the exine, and only in small quantities on the surface of the exine itself.
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10.
In fully developed parts of thalli ofLempholemma botryosum a relatively high number of algal cells is attacked by haustoria. They differ specifically in form and effect from haustoria of otherLempholemma species. Cells of theNostoc phycobiont attacked by hyphae developing into haustoria may divide to give inequal besides equal daughter cells.
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11.
Radiant umbels result from the enlargement of peripheral phyllomes. We find the following patterns: 1) TheOrlaya-type: only one petal in the flower is enlarged. 2) TheCoriandrum-type: one whole and two half petals in the flower are enlarged. 3) TheArtedia-type: two half petals in the flower are enlarged. 4) TheXanthosia-type: the enlargement affects three involucellar bracts of which two become asymmetrical.—The enlargement of the phyllomes can effect the umbellet or the umbel or both. Obviously, this is the reason why many of these inflorescence systems display insufficient degrees of synorganization, with an optimum reached inArtedia and some species ofXanthosia.
Herrn Univ.-Prof. Dr.Walter Leinfellner zum 70. Geburtstag gewidmet.  相似文献   

12.
TheSimaroubaceae generally have no true stipules. The stipule-like appendages of some genera proved to be pseudo- or metastipules (Weberling & Leenhouts 1965). There seem to be some exceptions, however: the generaCadellia (incl.Guilfoylia) andRecchia on the one hand, and theIrvingioideae on the other. As these taxa, with exception ofRecchia, have simple leaves, there are no indications that their stipule-like appendages might be pseudo- or metastipules. In regard to their position and ontogeny these appendages behave completely like true stipules. Assuming the view ofForman, one could conceive a morphological line from the long, broadly inserted axillary stipules of mostIrvingioideae to the small scaly triangular stipules ofIxonanthoideae. The similarities between the stipules ofIrvingioideae andErythroxylaceae (already emphasized byHallier and others), become even more evident when their ontogeny is investigated. TheIrvingioideae, therefore, might be regarded as a separate family (perhaps with some relation to theErythroxylaceae,Hallier) or as a subfamily ofIxonanthaceae (Forman).—In addition to data on stipules some results on the palynology and shoot anatomy of the generaCadellia (incl.Guilfoylia) andRecchia are reported. Their relationship with theSimaroubaceae also appears doubtful. If they are to be included, they represent a somewhat isolated group near the base of the family which otherwise has lost its stipules.
Herrn Univ.-Prof. Dr.Walter Leinfellner zum 70. Geburtstag gewidmet.  相似文献   

13.
The epidermal nuclei of the ovary inLinaria vulgaris andL. alpina, and the nuclei in leaves ofIncarvillea variabilis often contain crystalloid, tubular inclusions. The tubuli in bothLinaria species have an average diameter of 200 Å with a width of 70 Å in the clear and are arranged in a higly organized manner: Parallel tubuli form layers which build up a crystal lattice. There are three directions of tubuli in each inclusion: In each layer they are aligned in an angle of 60° to those of the next, so that the tubuli of the fourth layer are in the same direction as those of the first one. InIncarvillea the tubuli (each with an average diameter of 220 Å, and 70 Å width in the clear) also exhibit compact packing, but their arrangement is not so highly ordered as inLinaria.
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14.
Monsonia nivea is a hemicryptophyte which shows spiny petioles after the loss of leaf blades. Anthocladial inflorescences and their supporting vegetative parts are spineless. Spines are formed only by vigorous rosettes. Similar spiny petioles can be found in all other genera of the tribeGeranieae.
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15.
Transfer of fresh pollen either by wind or by insects is strongly related to the degree of its stickiness. The sticky substances involved should be understood as pollenkitt. Ultrastructural investigations indicate that the sticky pollen of entomophilous angiosperms (in this publicationHamamelis vernalis andH. virginiana, Corylopsis platypetala) results from the deposition of usually electron-dense, homogeneous pollenkitt mainly on the outside layer of the exine. In contrast, the pollen of anemophilous angiosperms (in this publicationParrotia persica, Platanus orientalis, Thalictrum flavum andQuercus robur), but also of some entomophilous angiosperms with special pollination ecology (e.g.Aquilegia vulgaris) is rather dry and powdery. In these cases the pollenkitt often is electron-transparent and inhomogeneous and is mainly removed into the cavities of the exine. Ultrastructure and deposition of pollen and pollenkitt in ambophilous angiosperms (in this publicationThalictrum minus, Castanea sativa) are ± intermediate.
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16.
This paper deals with a filamentousCyanophycea from aSphagnum bog whose position in the current system is dubious. A characteristic feature, among others, is a certain rhythm of cell division and bipartition of the filaments. As a consequence, only 8-, 16- and 32-celled filaments are present in the population. An occasional disturbance of the rhythm is transitory. In the longitudinal direction the filaments exhibit mirror symmetry in regard to their middle.
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17.
Placidiopsis pseudocinerea is described as a new species, which up to now is known from six localities in the Alps and northern Norway. The species is morphologically and anatomically very similar toCatapyrenium cinereum (Pers.)Koerb. but differs in having two-celled spores.
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18.
Zusammenfassung Markiertes Glycin und Serin wurde in Ferrichrom, Ferricrocin und Ferrichrysin von vier Stämmen der Gattung Aspergillus zu 1,6–11,8% in vivo eingebaut. Von Aspergillus fumigatus und A. quadricinctus wurden zellfreie Extrakte hergestellt, die Cyclohexapeptide synthetisieren können.
Incorporation of glycine and serine in sideramines of the ferrichrome type with fungi of the genus Aspergillus in vivo and in vitro
A 1.6–11.8% incorporation of labelled glycine and serine into ferrichrome, ferricrocin and ferrichrysin has been achieved with four strains of Aspergillus in vivo. Cell-free extracts of Aspergillus fumigatus and A. quadricinctus capable of cyclohexapeptide biosynthesis have been prepared.
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19.
The DNA of Blue-Green Algae may be specifically and most efficiently elucidated by the combined use of the fluorochrome DAPI and DNAse treatment. InChroococcus turgidus andSynechococcus aeruginosus it forms a network which usually is positioned at the periphery of the centroplasm. At the beginning of cell division it seems to be invaginated by the ingrowing cell wall. Later it must be distributed by other means because two equal parts are connected by a number of fine and straight DNA threads. InOscillatoria limosa usually all parts of the centroplasm are interspersed with the DNA network. In surface view, the DNA occasionally seems to consist of a number of independant rods, but in reality these are connected to the general network. Division apparantly occurs by ingrowth of the crosswall and usually results in equal daughter nuclear equivalents although occasionally they are unequal. Four strains ofMicrocoleus vaginatus were found to have nuclear equivalents of the same general appearance as inOscillatoria limosa.
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20.
As a rule,Gentianaceae exhibit a double unilacunar nodal pattern. Upon leaving the lacun, the complex leaf trace divides first into three branches, and then into five or more bundles which become the leaf veins. OnlyGentiana lutea (andG. punctata) as well asMenyanthes trifoliata differ from all other species investigated by their multilacunar nodes. BothCentaurium andOrphium within the cortex form a completely closed bundle ring around the nodal flanks from smaller bundles which depart from the lateral branches of the complex leaf traces.
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