摘要:

Pollen grains ofBorago officinalisL. were studied with transmission and scanning electron microscopy. Their main features are: (1) tectum covered with microsculptured gemmae, (2) apertures very elaborated, each of them is composed of a colpus (ectoaperture), a pericolpal cavity which occurs in the foot-layer, a mesoaperture localized within the endexine and a discontinuous endoaperlure displaying an equatorial girdle, (3) a discontinuity between ectexine and endexine which is electron transparent in the young microspore.

ISSN:0017-3134    

DOI:10.1080/00173138409428873

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Twenty species belonging to the six genera of Monimiaceae from the Malagasy region (southwest Indian Ocean) are examined and described palynologically. Phylogenetic relationships of the genera are discussed. Pollen morphological evidence is supportive of existing floral morphological and anatomical evidence and suggests the following conclusions: 1),Monimia(Monimioideae sensu Thorne) is not closely allied to the other five genera in the region (all Mollinedioideae sensu Thorne); 2)EphippiandraandHedycaryopsisappear to be more closely allied to each other than to the remaining genera; 3),Tambourissapollen displays a wide range of exine patterns which readily accomodates the pattern found inPhanerogonocarpus. Thus, pollen morphological evidence fails to support the continued generic segregation ofHedycaryopsisfromEphippiandra, and ofPhanerogonocarpusfromTambourissa.

ISSN:0017-3134    

DOI:10.1080/00173138409428874

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

To ascertain whetherCasuarina(not indigenous in Africa at present) did indeed occur in the Tertiary of South Africa, a comparative investigation of fossil pollen from the southwestern Cape and recent pollen ofCasuarina(Casuarinaceae, eight species),Gymnostoma(Casuarinaceae, one species) andMyrica(Myricaceae, ten species) was carried out at LM, SEM and sometimes TEM levels. The result of this study has established a definite significant distinction between the pollen morphology ofCasuarinaandMyricaat the generic level. The most important differences concern the apertures, the sculpture and structure of the exine. On the basis of the differences it has been established that bothCasuarinaandMyricapollen is abundantly present in the core of Tertiary age from The Southwestern Cape. The occurrence ofCasuarinapollen, together with other ancient extinct pollen types in the deposits at the Cape lend support to the hypothesis that a widespread common South American-Antarctic-African-Madagascar flora existed in the Gondwana fragments in the Cretaceous.

ISSN:0017-3134    

DOI:10.1080/00173138409428875

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A program aimed at making measurements principally of biological particles (pollen, spores, bacteria) at the ground and aloft over an extended grassland region, was performed in the neighborhood of Miles City, Montana, during the period of operation of Project CCOPE a large multiinstitutional field study of the characteristics of convective storms. Project CCOPE offered a large framework of measurements of atmospheric parameters useful for the interpretation of measured concentrations of biological particles and their behavior in height and time. The measurements carried out are being studied in relation to air trajectories, air mass changes, and the known distribution of sources of detected particles. Analysis of filter samples performed between ground level and 6000 m height revealed significant concentrations of biological particles at all heights, and some interesting observations of transport of non-biological particles emitted by a coal-fired power plant to at least 6000 m. Some meteorological explanations of the observations are offered.

ISSN:0017-3134    

DOI:10.1080/00173138409428876

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Three sampling techniques were used to determine how pollen concentrations obtained from atmospheric sampling devices compare to pollen concentrations in the home environment. Burkard pollen samplers were placed on rooftops at 4 locations in Tucson, Az. (USA) to sample regional atmospheric pollen; nearby, Rotorod® (rotorod) samplers collected atmospheric pollen in the home environment at 55 locations for 3 consecutive days during each season. Pollen concentrations from rotorod and Burkard traps show that pollen is rare inside homes and only occurs when pollen production is high. No differences in pollen concentration were found between rooms of any home, and frontyards generally had higher pollen concentrations than backyards. Pollen concentrations near homes were generally lower than regional pollen concentrations. Correlations were low even though pollen taxa were similar. Floor sweepings from homes contained pollen concentrations as high as 5.5 million pollen grains/g house dust. We conclude that little or no pollen gets inside houses through atmospheric transport. Pollen is most likely carried into the houses on the feet and bodies of people and pets.

ISSN:0017-3134    

DOI:10.1080/00173138409428877

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue

ISSN:0017-3134    

DOI:10.1080/00173138409428872

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor