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1.
Robert L. Dressler 《Brittonia》1968,20(2):182-190
New species ofBletia from Mexico are described and illustrated:B. concolor, B. similis, andB. urbana. The identity ofB. campanulata Llave & Lex. is discussed, andB. reflexa Lindl. is considered to be a distinct species. Several South American epithets are treated as synonyms ofB. campanulata. A key to the recognized species ofBletia is given. 相似文献
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Nodule samples were collected from four alder species:Alnus nepalensis, A. sibirica, A. tinctoria andA. mandshurica growing in different environments on Gaoligong Mountains, Yunnan Province of Southwest China and on Changbai Mountains, Jilin Province of Northeast China. PCR-RFLP analysis of the IGS betweennifD andnifK genes was directly applied to unculturedFrankia strains in the nodules. A total of 21 restriction patterns were obtained. TheFrankia population in the nodules ofA. nepalensis had the highest genetic diversity among all fourFrankia populations; by contrast, the population in the nodules ofA. mandshurica had the lowest degree of divergence; the ones in the nodules ofA. sibirica andA. tinctoria were intermediate. A dendrogram, which was constructed based on the genetic distance between the restriction patterns, indicated thatFrankia strains fromA. sibirica andA. tinctoria had a close genetic relationship.Frankia strains fromA. nepalensis might be the ancestor ofFrankia strains infecting otherAlnus species. From these results and the inference of the ages ofAlnus host species, it is deduced that there was a co-evolution betweenAlnus and its microsymbiontFrankia in China. 相似文献
3.
G. L. Hennebert 《Antonie van Leeuwenhoek》1967,33(1):333-340
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J. D. Currey 《Pal?ontologische Zeitschrift》1961,35(3-4):187-190
The analysis byØrvig of the structure of the scales ofScanilepis andOrvikuina is discussed. It is shown that the analysis, because it ignores the physical size of the scales, incorrectly leads to the conclusion that the scales ofOrvikuina show a stage of specialisation towards the higher teleostean condition further than, but of the same kind as, that shown byScanilepis. The specialisation ofOrvikuina is in fact of a different kind from that ofScanilepis. 相似文献
5.
Ghillean T. Prance 《Brittonia》1968,20(3):203-204
Maranthes, a genus well known in Africa and Asia, has not been recorded previously in the New World.Couepia panamensis, thought to be endemic to Panama, was found to be synonymous withMaranthes corymbosa, a widespread Asiatic species, and it is reduced into synonymy, making the first American record ofMaranthes. The relationship ofMaranthes toCouepia, and the unusual distribution ofM. corymbosa are discussed. 相似文献
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Flow cytometry was used to determine ploidy levels in the Czech and Slovak taxa of the genusPseudolysimachion (W.D.J. Koch)Opiz (=Veronica auct. p.p.,Scrophulariaceae). In total, 123 populations from the Czech Republic, Slovakia, Ukraine (one locality), Austria (one locality) and Hungary (one locality) were analyzed. InP. maritimum (L.)Á. Löve etD. Löve andP. spicatum (L.)Opiz, two cytotypes were found: diploid (2n=2x=34) and tetraploid (2n=4x=68). In both species the tetraploid cytotype predominated (P. maritimum: 41 tetraploid populations out of 45;P. spicatum: 57 tetraploid populations out of 58). The two cytotypes ofP. maritimum have no taxonomic significance because ploidy level is not obviously correlated with morphology, distribution pattern or ecology. Tetraploid populations ofP. spicatum belong to two morphologically different subspecies, subsp.spicatum and subsp.fischeri Trávní?ek. The diploid cytotype (one population only) should be provisionally classified as a third subspecies ofP. spicatum, which is morphologically similar to the Asian subsp.porphyrianum (Pavlov)Trávní?ek. Only diploid plants (2n=2x=34) ofP. orchideum (Crantz)Wraber were found; all 13 populations that were analyzed belong toP. orchideum s.str. One diploid population sample ofP. spurium subsp.foliosum (Waldst. etKit.)Holub (2n=2x=34) and one tetraploid sample ofP. incanum subsp.pallens (Host)Trávní?ek (2n=4x=68) were also analyzed. In addition, three tetraploid populations of hybrid origin were investigated:P. maritimum ×P. spicatum subsp.spicatum (one population) andP. maritimum ×P. spurium subsp.foliosum (two populations). While hybrid plants ofP. maritimum ×P. spicatum arose from tetraploid parental species, plants ofP. maritimum ×P. spurium probably resulted from a cross between tetraploidP. maritimum and diploidP. spurium. The putative origin and evolutionary importance of polyploids in thePseudolysimachion are discussed. 相似文献
7.
Maxim K. Elias 《Pal?ontologische Zeitschrift》1962,36(1):29-37
The type specimen ofGonioloboceras goniolobum (Meek), rediscovered by Spath in the British Museum, is the foundation for a more accurate comparative study of this and other species ofGonioloboceras.Gonioloboceras described asG. goniolobum byElias in 1938 is differentiated asGonioloboceras schmidti, new species. Suture sets (new term) for several growth stages inG. goniolobum (Meek),G. welleriSmith,G. schmidtiElias, G.eliasiMiller &Owen, andG. asiaticumLibrovitch are assembled and used for differentiation of the species.The Kazakhstan goniatite faunule containingG. asiaticum is considered of very late Pennsylvanian age. 相似文献
8.
Zdeněk Urban 《Folia Geobotanica》1967,2(2):189-196
Puccinia tatrensis Urban onGeum reptans in Czechoslovakia is recognized as a subspecies ofPuccinia sieversiae Arth.Puccinia waldsteiniae, P. gei andP. gei-parviflori appear to be the most ancient rusts known on the tribeGeeae and it is assumed that their common ancestral form was already present in the Cretaceous period.Puccinia sieversiae is more advanced and has its centre of origin and spread in Central Asia. Phylogenetically most advanced and at the same time most differentiated from each other are species ofPhragmidium, i.e.P. circumvallatum andP. miyabeanum. 相似文献
9.
Bernard Krebs 《Pal?ontologische Zeitschrift》1967,41(1-2):46-59
Up to nowMachimosaurus was known only from isolated teeth. Its systematic position was uncertain. Recently discovered remains ofMachimosaurus from the Upper Jurassic of Portugal allow a reconstruction of the skull. This find proves thatMachimosaurus belongs to the crocodilian family Teleosauridae. The genus comprises the only speciesMachimosaurus hugii H. v.Meyer. The speciesMachimosaurus mosae Sauvage & Liénard is based on heterogeneous material and is unmaintainable. Osteological characteristics show that the environment ofMachimosaurus was the open seas. 相似文献
10.
Alcantarea turgida andA. tortuosa are described and illustrated as new species from southeastern Brazil. The relationships ofA. turgida withA. extensa and withA. vinicolor and ofA. tortuosa withA. farneyi and withA. benzingii are discussed. 相似文献
11.
Otto Linck 《Pal?ontologische Zeitschrift》1963,37(3-4):268-276
Notice is given of the first skull-bones ofCeratodus rectangulus Linck found in the Germanic Trias; they have been compared with those ofC. sturii Tell. and the recent genusEpiceratodus. The number of fossil teeth ofCeratodus is much larger, relatively, than that of the bones of the skull. This is explained by the assumption that these dipnoans were not embedded in their natural biotops. 相似文献
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Two hundred and thirteen fungal cultures were recovered from 88 soil samples from different parts of Indonesia; 39.4% belonged to the genusPenicillium, 19.7% to the genusAspergillus, 9.9% to the genusFusarium and the rest to different systematic groups. One hundred and fifty two cultures were antibiotically active; 80% of these were antagonists ofBacillus subtilis, 55% ofEscherichia coli, 20% ofSaccharomyces cerevisiae and 37% ofCandida pseudotropicalis. In agreement with previous observations it was found that the activity spectrum of antagonists was related to the altitude above sea level at which they were found. As the altitude increased, the incidence of antagonists with both antibacterial and antifungal activity decreased, but the incidence of antagonists with only antibacterial or only antifungal activity increased. Fungi of the generaPenicillium andAspergillus were the most frequent antibiotic producers. The incidence of penicillin producers was much lower than in collections of fungi isolated in higher latitudes (China, Bulgaria, Slovakia). 相似文献
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15.
Gerald B. Ownbey 《Brittonia》1968,20(4):336-342
Data on chromosome numbers in eleven species and three forms ofCirsium are presented. The species treated areC. nivale (H.B.K.) Schultz Bip.,C. jorullense (H.B.K.) Spreng.,C. durangense (Greenman) Ownbey,C. ochrocentrum Gray,C. undulatum (Nutt.) Spreng.,C. velatum (Wats.) Petrak,C. mexicanum DC.,C. rhaphilepis (Hemsley) Petrak,C. occidentalis (Nutt.) Jepson subsp.acrolepis Petrak,C. conspicuum (Sweet) Schultz Bip., andC. ehrenbergii Schultz Bip. A case of autotriploidy is reported forC. durangense. Natural hybridization betweenC. durangense and a form ofC. mexicanum is reported. Photomicrographs of the mitotic or meiotic chromosomal configurations of nine species and two forms are reproduced.C. ochrocentrum Gray var.durangense Greenman is raised to species rank. 相似文献
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Chromosome numbers for 98 plants ofF. pallens, 19 ofF. psammophila, F. belensis andF. vaginata, and 44 ofF. ovina (originating from Austria, the Czech Republic, Germany, Slovakia and Latvia) are given. In addition to theF. ovina andF. pallens groups, chromosome counts for the following taxa are also reported:F. alpestris (2n=14) reported for the first time in this work,F. amethystina subsp.amethystina (2n=28),F. brevipila (2n=42),F. cinerea (2n=28),F. rupicola subsp.rupicola (2n=42) andF. versicolor subsp.versicolor (2n=14).InF. pallens, two ploidy levels (2n=2x=14+0-1B, 2n=4x=28+0-1B) as well as two natural triploid plants (2n=21+0-1B), were found. In addition to the fourF. pallens types that have been distinguished in Austria, one new tetraploid type (F. pallens “scabrifolia”) from the Czech Republic and Germany is reported and its taxonomy is discussed. The distributions of the Oberösterreich-Niederösterreich and Pannonisches-HügellandF. pallens types outside of Austria are documented.Only the diploid chromosome number (2n=14) was found inF. psammophila andF. vaginata. Chromosome numbers forF. psammophila subsp.muellerstollii andF. belensis (both 2n=14) were determined here for the first time. Two ploidy levels, 2n=14+0-5B corresponding toF. ovina subsp.ovina and 2n=28 corresponding toF. ovina subsp.guestphalica andF. cf.duernsteinensis were confirmed inF. ovina. Differences in chromosome structure (simple and multiple secondary constrictions) betweenF. pallens as opposed toF. psammophila andF. vaginata are discussed. A complete survey of published chromosome counts for Central European species from theF. ovina andF. pallens groups is included. 相似文献
19.
Josef Měsíček 《Folia Geobotanica》1967,2(4):433-436
The chromosome number ofA. thaliana from three localities in Central Bohemia was found to be 2n=10. All the chromosomes (length 1,5–2,6μm) belong to the atelocentric type, four pairs (m) having the centromere in the median and one pair (sm) in the submedian region. In connection with the discussion on the origin ofH. suecica the author presents the following preliminary results: a) the failure to cross the tetraploidCardaminopsis arenosa (L.)Hayek withA. thaliana; b) the successful crossing of the diploidC. petraea (L.)Hiit. withA. thaliana; c) the discovery of a diploid population ofC. arenosa (2n=16) in the Tatra Mts. (Czechoslovakia). 相似文献
20.
Jiří Soják 《Folia Geobotanica》1966,1(1):341-355
Five new species and two varieties from the sectionMultifidae are described from the Sino-Himalayan region. They are referred to the affinity ofP. multifida L. andP. griffithii Hook. f.; one of the new species is probably related toP. gerardiana Lindl. and one is intermediate between the species of the sectionsMultifidae andNiveae. 相似文献