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1.
The phycobiont ofCatolechia wahlenbergii belongs to a new genus of theChlorococcales. It has mostly ellipsoidal, more rarely spherical cells with one bilobate through-shaped chloroplast and in general alveolar cytoplasm. Reproduction occurs by 2 or 4 autospores as well as by 16 or 32 motionless, small rodlike spores, which are formed and released in the same way as zoospores. They are aplanospores, and their formation apparently is fixed genetically, and not modificatorily, as in other species.
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2.
Asperula visianii Korica is described as a new stenoendemic species from the small Central Dalmatian island of Svetac (near Vis). It differs in several morphological features (which remain constant in cultivation) and in its ecology from the closely relatedA. staliana Vis., endemic on the nearby island of Bievo.
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3.
The frutescent species of the lichen genusCaloplaca are usually united in sect.Thamnoma, but they do not form a natural group. They are derived from different species groups within sect.Gasparrinia from different parts of the world, presumable from species having scleroplectenchymes in cortex and medulla. The algal cells are concentrated between the scleroplectenchymatic strands in large and dense groups, from where medullary plectenchyme extends to the cortex and forms characteristic pseudocyphellae there.—Most of the species seem to be ornithocoprophilous; they grow on rocks along marine coasts where much fog is induced by cold currents.—Caloplaca cribrosa is endemic in Tasmania and New Zealand,C. regalis and the doubtfulC. ambitiosa belong to the antarctic element.C. fragillima from central Chile seems to be propagated by thallus fragments.C. coralloides andC. thamnodes are endemic to California and Baja California respectively.C. cladodes from the Rocky Mountains deviates in many characteristics from the other species i.a. by it different ontogenetic development, reduced spore septum, and cementing amyloid polysaccharides within the scleroplectenchymatic strands. The African species are characterized by their distinctly dorsiventral lobes and usually possess oil cells in some of the paraphyses.Caloplaca bonae-spei, C. fragillima andC. thamnodes are new to science.
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4.
The following new hybrids are described:Euphrasia ×dilata = E. hirtella Jordan exReuter ×alpina Lam.;Euphrasia ×trikoviana = E. tricuspidata L. ×rostkoviana Hayne. The chromosome number ofEuphrasia tricuspidata L. has been established for the first time: 2n = 22.
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5.
Population analyses, scatter diagrams and field observations demonstrate thatOphrys helenae is morphologically (and ecologically) well separated from the partly sympatricO. mammosa andO. ferrumequinum in N. Greece. Hybrids with the distantly relatedO. mammosa are very rare.
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6.
The following species are described as new:Anthemis mazandaranica in N. and NW. Iran is allied toA. coelopoda; A. moghanica in NW. Iran is close toA. candidissima andA. sintenisii; A. atropatana also in NW. Iran is similar toA. hyalina; A. gracilis in W. Iran is close toA. plebeia; A. bushehrica in SW. Iran is similar toA. susiana; andA. rhodocentra in S. and E. Iran and in Pakistan is akin toA. austro-iranica, A. gayana, andA. kandaharica.
Anschrift des Herausgebers: Hofrat Univ.-Prof. Dr.Karl Heinz Rechinger, Beckgasse 22, A-1130 Wien, Österreich.  相似文献   

7.
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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8.
Morphological and cytological investigations as well as crossing experiments were carried out withRanunculus seguieri Vill. and 4 species of theRanunculus alpestris L. group (R. alpestris L.,R. traunfellneri Hoppe,R. bilobus Bertol.,R. crenatus Waldst. & Kit.). ForR. seguieri andR. alpestris, localities and distribution are given in addition to extensive diagnoses. A key to the species includes morphological characteristics and distribution data forR. traunfellneri, R. bilobus, andR. crenatus. New diagnostic characters are described. Crossing experiments betweenR. seguieri and the species of theR. alpestris group were unsuccessful. All 5 species have a chromosome number of 2n = 16, the record forR. bilobus is new. There is no statistically significant difference between the karyotypes ofR. seguieri andR. alpestris s. str. Nevertheless, according to morphological evidence and crossing experiments,R. seguieri is not closely related to theR. alpestris group.
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9.
Theligonum cynocrambe and 13 species ofRubiaceae contain S-type sieve-element plastids, wide-spread in Dicotyledons. Alignment ofTheligonum toCaryophyllales (Centrospermae), especiallyPhytolaccaceae, is unlikely, because this order is characterized by specific P-type plastids. SEM investigations show the pollen exine ofTheligonum to be microreticulate, with additional supratectate spinules.Asperula and other genera of the tribeRubieae have a tectum perforatum (punctitegillate sexine), also with supratectate verrucae or spinulae.—Thus ultrastructure suggests (but not definitely proves) relationships betweenTheligonum andRubiaceae, while affinities betweenTheligonum andCaryophyllales are excluded.
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10.
In theChrysophyceae as well as in different species ofCryptomonas bilobed chromatophores are present. These chromatophores consist of two large parietal lobes closed to the lateral sides of the cell and joined by a narrow bridge on its dorsal part. A survey of all species with a single bilobed chromatophore is given. Besides, also species with two separate chromatophores have been found. The presence of several chromatophores inCryptomonas cells is doubtful. The morphology of the chromatophores has to be taken into consideration in the taxonomy ofCryptomonas.
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11.
Rumex bithynicus sp. n. (sect.Rumex) with two new hybrids from NW Turkey is close toR. alveolatus (from NE Iran, Afghanistan, NW Pakistan and Turkmenistan).
Beiträge zur Kenntnis der GattungRumex XVIII. — Übersicht über die vorhergehenden Beiträge siehe Nuytsia (Perth, W-Australien)5, 75–122 (1984).  相似文献   

12.
Achnanthes linearis produces two auxospores from one cell pair by allogamic fusion of migratory and stationary gametes. Unusually little copulation jelly is produced. Pairing occurs by chance in regard to the heteropoly of the transapical axis. The orientation of the primary cells in relation to the substratum and to the mother cells is constant and characteristic. Variation of cell size is much larger than hitherto known; correspondingly the diagnosis is to be completed.—The position and orientation of vegetative cells and partner cells is strongly determined by the relief of the leaves ofFontinalis on which they are fixed with their raphe valve. The same is true for the cells ofA. minutissima which usually are fixed at one cell pole only, but exceptionally at both poles; this means that morphological heteropoly of apical axis is lacking, and that the function of the second holdfast-jelly producing structure usually is suppressed. The cells of both species normally creep by means of the raphe mechanism; the direction is very independent of the relief of theFontinalis leaves. After cell division the moving down of the upper daughter cell follows a different mechanism.A. linearis is the first to settle onFontinalis leaves, other epiphytes come much later.
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13.
Proterospores are formed exclusively at the beginning of the sporulation period and independently of abiotic factors. They differ both morphologically and physiologically from other spores developed later by the same fruit-body. As seen inGanoderma, proterospores germinate readily, whereas other spores must first pass through a fly larva gut. These proterospores are therefore well adapted to dispersal by air, the other spores, however, to dispersal by animals. In this respect, ontogenesis appears to recapitulate phylogeny. A comparative study of proterospores should further clarify systematic relationships within the fungi.
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14.
The chromosome numbers of five species ofOrobanche sect.Orobanche (O. alsatica, O. laserpitii-sileris, O. loricata, O. salviae, O. teucrii) are reported for the first time and previous counts could be verified in ten other species. Now the chromosome numbers of all species of sect.Orobanche occurring in Central Europe are known: they are diploid (2n = 38) with the exception ofO. gracilis (tetra- and hexaploid, aneusomatic).
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15.
Morphological and cytological investigations as well as crossing experiments were carried out with the 5 species of theRanunculus alpestris group (R. alpestris L.,R. traunfellneri Hoppe,R. bilobus Bertol.,R. crenatus Waldst. etKit.,R. magellensis Ten.). A key to the species is presented; localities and distribution are given in addition to extensive diagnoses. Crossing experiments between the 5 taxa were successful (F1-F3 individuals, backcross types, tripeland quadrupelbastards); the morphology of the experimentally obtained F1-hybrids was mostly intermediate. All 5 species as well as all hybrids have a chromosome number of 2n = 16; there is no statistically significant difference between the karyotypes of the 5 taxa. According to the results of the morphological investigations and the crossing experiments we can distinguish 2 subunits of very closely related species: a)R. alpestris, R. traunfellneri, R. bilobus; b)R. crenatus, R. magellensis. The speciation within the group ofRanunculus alpestris is discussed.
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16.
The MediterraneanOrobanche variegata has n = 38. This is the third tetraploid taxon known from sect.Orobanche.
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17.
Saponaria stenopetala sp.n. in Eastern Afghanistan is close toS. pachyphylla Rech. f. andS. subrosularis Rech. f.—The nearest allies ofS. makranica sp.n. from Western Pakistan and Southeastern Iran areS. kermanensis Bornm. andS. floribunda (Kar. & Kir.)Boiss.
Flora Iranicae praecursores 36–37. — Praecursores praecurrentes in Pl. Syst. Evol.139, 313–317 (1982).  相似文献   

18.
If exsiccated trichomes ofPseudanabaena galeata are immersed in water, striking changes occur as a consequence of lysis and maceration. The locomotion of living trichomes differs from that inOscillatoriaceae. This and other differences make it doubtful, whetherPs. galeata belongs to theOscillatoriaceae; at any rate it occupies an aberrant position.
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19.
Zusammenfassung Die Spermatiden von Spirostreptus spec. bleiben während der ersten Phasen der Spermiohistogenese durch Zellbrücken miteinander verbunden. Im Bereich der Brücke tritt ein Phragmoplast auf, der zuerst aus Zwischenspindelfasern, einem regelmäßigen Netzwerk endoplasmatischen Retikulums und aus einem kugeligen osmiophilen Körper besteht. Die osmiophile Substanz wird stark vermehrt und erstreckt sich in die Zellbrücke, während das endoplasmatische Retikulum dort verschwindet. Vor der Durchtrennung der Zellbrücke ziehen sich das granulierte Material und die Spindelfasern aus der Zone der trennenden Zellmembran zurück. Dort erscheinen dann Bläschen und konfluieren zu den Zellmembranen.
The phragmoplast in the spermatides of Spirostreptus spec. (Myriapoda, Diplopoda)
Summary During the early phases of the spermiohistogenesis the spermatides of Spirostreptus spec. are connected by cell bridges. In the region of the bridge a phragmoplast appears which at first consists of continuous spindle fibres, a regular network of endoplasmatic reticulum and a spheric osmiophilic body. The osmiophilic substance increases and extends into the cell bridge while the endoplasmatic reticulum is disappearing there. Before the cell bridge is divided the granulated material and the spindle fibres retract from the zone of the separating cell membrane. Then there are appearing vesicles which fuse to the cell membrane.
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20.
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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