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1.
A partial mandible with two molars intact was recovered between 1981 and 1984 from deposits of the Middle Pliocene at Tabarin, in Kenya. It has been described and assigned toAustralopithecus cf.afarensis Johanson, White, andCoppens, 1978, with the condition that if ‘A. afarensis’ is revised, then the attribution may change. The taxon ‘A. afarensis’ was found to be invalid and was revised. The smaller specimens of ‘A. afarensis,’ to which the Tabarin mandible was said to be similar, were redescribed asHomo antiquus Ferguson, 1984. Since the Tabarin mandible andH. antiquus are successive transients of the same gens and are allopatric, the Tabarin hominid population is described as an earlier chronosubspecies,Homo antiquus praegens ssp. n.  相似文献   

2.
Specimens of the larger Neogene porcupines, generally allocated toHystrix primigenia (Wagner, 1848), from 17 localities are studied, and their taxonomic status is recon-sidered. Material from one of these localities has recently been described asHystrix depereti Sen, 2001. The diagnoses of both species are revised. Tooth size and crown height are considered diagnostic characters at the species level. As a resuit, specimens from eight localities are allocated toH. primigenia, from eight other localities toH. depereti, and from one locality toHystrix sp. indet. The level of specialisation of the cranial morphology of these fossil species is compared withH. refossa Gervais, 1852 and with extant species. Diagnostic characters ofH. aryanensis SEN, 2001 and ofH. zhengi van Weers & Zhang, 1999, are discussed.  相似文献   

3.
Summary A. According toMellon,Locke andShinn, the bacteriostatic action of sulfanilamide is due to the inactivation of (bacterial) catalase and the resulting accumulation of hydrogen peroxide. The probability of this theory is discussed. B. Catalase activity was studied by means ofPhotobacterium Fischeri, as an oxygen indicator. By adding hydrogen peroxide to the tested cultures of bacteria it has been demonstrated, that: I.Bacterium coli, Photobacterium Fischeri andStreptococcus haemolyticus (strainAronson) contain catalase. II. Sulfanilamide does not inactivate the catalase in blood. III. Sulfanilamide does not inactivate bacterial catalase nor does it affect the production of catalase in the growing culture containing the drug. So we have to conclude that the assumption of catalase inactivation to be the essential factor in sulfanilamide action on bacteria will not lead us to the solution of the problem. First communication:L. K. Wolff andH. W. Julius, Ann. de l'Inst. Pasteur62, 616, 1939.  相似文献   

4.
A fossil skull, Stw 53, from the Plio/Pleistocene of Sterkfontein, in South Africa, has been referred toHomo habilis Leakey, Napier, andTobias, 1964. Reappraisal of its putative hominine affinity reveals a closer resemblance toAustralopithecus africanus Dart, 1925. The skull, as reconstructed, is too small forH. habilis; with no indication of brain expansion overA. africanus; has a facial angle outside the hominine range, but identical with that ofA. africanus; and whose teeth are not elongated but display buccolingual expansion. Although it was found in the same strata (Member 5) as stone tools, there is no causal connection. It has been dated faunistically at 2–1.5 my BP, but due to an unconformity it is suggested that it could be older. In spite of its late date, Stw 53 shows no intermediate characters which could support a trend towardsH. habilis orA. robustus Broom, 1938. It may, therefore, represent a relict population ofA. africanus.  相似文献   

5.
Based on an analysis of results from experimental hybridization, the plants assigned byMunz toOenothera subg.Oenothera and subg.Raimannia, now divided into approximately 76 species, are referred to a single section,Oenothera. This section is in turn divided into five subsections:Euoenothera, Munzia, Raimannia, Emersonia, and an undescribed group of three species related toOenothera pubescens. Euoenothera is maintained in the traditional sense, and includes about 14 species of North America, widely naturalized elsewhere.Munzia consists of 45 species, comprising three series, and native to South America.Raimannia is restricted to a group of approximately 11 North American species.Emersonia comprises four rather heterogenous species of northern Mexico and southern New Mexico, of whichOenothera macrosceles, O. maysillesii, andO. organensis have been described. Within these four subsections, interspecific hybrids can be made in general, although plastid differentiation often leads to incompatibilities. With varying degrees of difficulty, hybrids were produced in all intersectional combinations involvingEuoenothera, Emersonia, Munzia, andRaimannia, the most difficult being those betweenEmersonia andRaimannia. Based on their habit and distribution,Emersonia species, and especiallyOenothera maysillesii, appear to resemble most closely the common ancestor of the section,Euoenothera andMunzia to have been derived from it or its common ancestor, andRaimannia perhaps to be more closely related to the phylogenetic branch that leads toEuoenothera.  相似文献   

6.
In 83 species of the familiesMonotropaceae, Apocynaceae, Oleaceae, Scrophulariaceae, Lentibulariaceae, Bignoniaceae, Martyniaceae, Myoporaceae, Verbenaceae, Lamiaceae, Campanulaceae, andLiliaceae, protein bodies in the cell nuclei have been found, in 68 of these species for the first time. On the basis of their structure in accordance with morphological characters the generaBurgsdorfia, Hesiodia, Olisia, andPhlomoides of theLamiaceae are accepted;Lamium is divided intoLamium, Lamiastrum andOrvala; two new combinations are established:Kickxia campyloceras (Rech. fil. &Esfandiari)Speta andEtornotus papilionaceus (Burm. in L.)Speta. Deviating shape or lack of protein bodies corroborate former taxonomic decisions, e.g. the transfer ofMonotropa toMonotropaceae or the separation ofGaleopsis andLadanum; Veronica schmidtiana should not be included inPseudolysimachion. Systematic affinities are discussed primarily withinScrophulariaceae because nuclear protein bodies have been studied already in many species of this family. ForCampanula patula two 2 x populations are reported.
Herrn Professor Dr. L.Geitler zum 80. Geburtstag gewidmet.  相似文献   

7.
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   

8.
Summary E. coli KB (Benzer) differs from other common laboratory strains in possessing a glycyl sRNA synthetase with a 50 to 100 times elevated K m for glycine. The degree of charging of glycyl sRNA in this strain can be increased by supplementing the growth medium with glycine. The altered enzyme has been used as a marker by which to map its structural gene. Linkage analysis of recombinants from uninterrupted matings, and cotransduction (80%) of the synthetase withxyl, indicate that this gene is located betweenxyl andmalt, close toxyl, at min 69.5 on the map drawn byTaylor andThoman (1964).  相似文献   

9.
Serum albumin (Alb) and erythrocyte adenosine deaminase (ADA) polymorphisms in Asian macaques were investigated by means of starch gel electrophoresis. The materials comprise a total of 2,323 blood samples from eight species, namely,Macaca fuscata,M. mulatta,M. cyclopis,M. fascicularis,M. nemestrina,M. speciosa,M. radiata, andM. assamensis. It was observed that three Alb phenotypes were controlled by two codominant alleles, Alb mac A and Alb mac B and six ADA phenotypes by four codominant alleles, ADA mac 1 , ADA mac 2 , ADA mac 3 , and ADA mac 4 . The taxonomic relationships amongM. assamensis,M. radiata, andM. mulatta were analyzed by measuring theNei's (1975) genetic distance. The result supportedHill andBernstein's (1969) postulation thatM. assamensis was more closely related phylogenetically toM. radiata than toM. mulatta.  相似文献   

10.
The bradoriid genusHipponicharion Matthew, 1886 is one of the oldest known Cambrian ostracods. Until now, five species have been documented and another three taxa have been tentatively assigned to one or another species.Hipponicharion has been recorded from Poland, Germany, Morocco as well as from Canada and Great Britain.Hipponicharion hispanicum n. sp. represents the first Cambrian ostracod documented from Spain.Hipponicharion taidaltensis n. sp., formerlyH. aff.geyeri Hinz-Schallreuter, 1993 andH. elickii n. sp., formerlyH. cf.eos sensuElicki, 1994 have also been restudied in this paper.Hipponicharion seems to be restricted to the Acadobaltic Province sensuSdzuy (1972). The systematic relationships of the Bradoriida, which is controverse, is briefly outlined, emphasizing close affinities to the Ostracoda.   相似文献   

11.
Eocryphops andPlagiolaria are revised and a new species,E. albertii, is described from the Eifelian of Morocco.“Trimerocephalus” cyclophthalmus Walther, 1907, a species long assigned toEocryphops, is regarded as a junior subjective synonym of the type species ofPlagiolaria, Pl, plagiophthalma. Eocryphops originated in the evolutionary lineage leading toPhacops (s.str.), whereasPlagiolaria was probably derived fromLochkovella. Although they have been linked with the Late Devonian group of small-eyed and blind phacopids includingCryphops and its relatives. neitherEocryphops norPlagiolaria is ancestral to these forms. Confirmed occurrences ofEocryphops andPlagiolaria are from regions that were situated on the North Gondwana margin or on plates associated with this margin.  相似文献   

12.
A new species,Thomsonia sumawongii Bogner, is described from Thailand. Relationships toTh. napalensis and betweenThomsonia, Pseudodracontium andAmorphophallus are discussed.Allopythion hookeri Schott has to be eliminated as dubious.
  相似文献   

13.
The genetic relationships ofAechmea mexicana, A. lueddemanniana, A. macvaughii andA. tuitensis were investigated using starch gel electrophoresis. Eight enzyme systems encoded by ten putative gene loci were resolved in seventeen populations.Nei's (1978) genetic distances were obtained from allelic frequencies and used with UPGMA algorithm. Results indicate that some populations belonging to different species display genetic similarities closer to each other than to some conspecific populations. Our results do not support the proposed genusUrsulaea (Read & Baensch 1994), sinceA. tuitensis was closer toA. lueddemanniana andA. mexicana than toA. macvaughii.  相似文献   

14.
Summary Adelocaryum anchusoides (Lindl.)Brand andA. capusii (Franch.)Brand are members of the genusLindelofia,A. Schlagintweitii Brand,A. erythraeum Brand,A. flexuosum Brand undA. malabaricum (C. B.Clarke)Brand are newly combined toCynoglossum, A. coelestinum (Lindl.)Brand is a species of subgenusEleutherostylum inCynoglossum in which genus it had already been placed byLindley.  相似文献   

15.
The serological investigations support the opinion ofJanchen (1942) to combine the generaBunias, Isatis, andSisymbrium in the tribeSisymbrieae; Cheiranthus, Erysimum, andMatthiola in the tribeHesperideae; andBrassica, Crambe, Sinapis, andSuccowia in the tribeBrassiceae. They further underline the central position of theSisymbrieae and the isolated position of theHeliophileae. In accordance withEigner (1973) theBrassiceae are placed closer to theSisymbrieae than inJanchen; the same holds for thePringleeae. No serological justification could be found to uniteArabis andBarbarea in the tribeArabideae, andAlyssum andLunaria in theAlysseae. From the antigen-systems used among the representatives ofJanchen's Lepidieae the generaLepidium andNeslia show remarkable correspondence both toCamelina andThlaspi, but not toCochlearia which appears distant fromCamelina andThlaspi also.
Teil 1/Part 1.  相似文献   

16.
Three species ofOcruranus Liu, 1979 are described from the Bastion Formation of North-East Greenland, of late Early Cambrian (middle Dyeran of North American usage) age, representing the youngest record of a genus originally described from the earliest Cambrian Meishucunian Stage of China. An accompanying species, tentatively assigned toXianfengella He &Yang, 1982, seems also to be present in South Australia in strata of late Early Cambrian (Botoman of Siberian usage) age, although also this genus was described originally from the Meishucunian.Ocruranus andXianfengella from China have been interpreted as possibly parts of coeloscleritophoran scleritomes, perhaps halkieriids, rather than individual molluscan shells. Their shell form is not typical of helcionelloids which otherwise dominate the Early Cambrian molluscan record, but conclusive evidence of affinity is not forthcoming from the Greenland records. New taxa:Ocruranus septentrionalis n. sp. andOcruranus tunuensis n. sp.   相似文献   

17.
A taxonomic reevaluation of two little-knownBrimeura taxa,B. fontqueri (Pau)Speta andB. duvigneaudii (L. Llorens)Rosselló et al., has been made.Brimeura fontqueri, described from the Iberian peninsula, has been put into synonymy ofB. amethystina (L.)Salisb., since it could not be distinguished on morphological, anatomical or cytogenetic grounds.Brimeura duvigneaudii, from the Balearic Islands, is closely related toB. amethystina and has 2n=28 chromosomes. It differs from the latter by its naked bulbs lacking dark cataphylls, and its narrower leaves and whitish corollas. Accessory chromosomes are reported for the first time in the genus. Karyological instability (with chromosome numbers ranging from 2n=28 to 42) is reported for a population ofB. fastigiata (Viv.)Chouard. A key to the recognized taxa ofBrimeura is provided.  相似文献   

18.
A parsimony analysis of DNA sequences of the chloroplast-encoded generbcL from twelve members of theAcanthaceae s.l., including members of the sometimes segregateThunbergioideae andNelsonioideae, and other families in theBignoniales sensuThorne (1992) is presented. The results largely agree with the classification of theAcanthaceae presented byBremekamp (1965) andThorne (1992) and supportNelsonioideae as a sister group to the rest of theAcanthaceae. Thunbergioideae are placed as a sister toAcanthaceae s.str.Acanthus andAphelandra, both representatives ofAcanthoideae, form a sister group toRuellioideae. An analysis of branch support found that many branches throughout theBignoniales are weakly upheld. This points to the need for further studies in the group using more sequences ofrbcL as well as other data. None of the families ofBignoniales as presently circumscribed (includingAcanthaceae s.l.) were strongly supported, although the larger clade containing the families of theBignoniales was robust.  相似文献   

19.
A specimen of the machaeridianLepidocoleus cf.ulrichi described herein focuses attention on taxonomical difficulties with extremely dorso-ventrally elongated sclerites found in some lepidocoleid taxa.Lepidocoleus ulrichi Withers, 1926 andLepidocoleus sigmoideus Withers, 1926 exhibit very similar appearances and prove indistinguishable based onWithers 1926 criteria. The key to separating taxa as similar as these may instead lie in the most juvenile stages of growth.  相似文献   

20.
Kenneth D. Laser 《Protoplasma》1974,80(1-3):279-283
Summary The plastids in sieve tube members of the stamen vascular bundles ofSorghum bicolor, fixed in glutaraldehyde with postfixation in osmium tetroxide, are of the P-type containing cuneate crystalloids of a proteinaceous nature surrounded by a double envelope. Secondary inclusions are present in these P-type plastids. P-type plastids inSorghum often remain intact in the mature sieve tube members.This work was supported by a grant from the Iowa Agricultural and Home Economics Experiment Station, Ames, U.S.A. Project No. 1740 toHarry T.Horner, Jr., andNels R.Lersten and Project No. 1914 toHarry T.Horner, Jr. of the Department of Botany and Plant Pathology, Iowa State University, Ames, U.S.A. This work was completed by the author as part of the Ph. D. dissertation research.  相似文献   

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