Results 191 to 200 of about 39,574 (242)

Fossil Oculata Pollen from Alaska

Proceedings of the Annual Meeting. American Association of Stratigraphic Palynologists, 1976
Abstract Fossil pollen of the morphological type “oculata” have been encountered in sediments of Upper Cretaceous and Palaeocene age in Alaska. These Alaskan assemblages contain most of the species described by other authors in the United States, Canada, and the USSR. In addition, several new Alaskan species have been encountered.
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Triprojectate fossil pollen genera

Review of Palaeobotany and Palynology, 1990
Abstract Tripojectacites pollen, important age indicators for many Upper Cretaceous and Lower Tertiary strata in parts of the northern hemisphere, have been subjected to a variety of generic treatments sice their first formal description over 30 years ago.
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The fossil pollen record of Araceae

Plant Systematics and Evolution, 2006
The fossil record of Araceae pollen beginning in the late Early Cretaceous and peaking in the Paleocene/Eocene is very sparse up to now, consisting of three highly distinctive types: zona-aperturate pollen of the Monstera or Gonatopus type (very similar to Proxapertites operculatus), an ulcerate-spiny type typical for Limnobiophyllum, and a polyplicate,
Hesse, Michael, Zetter, Reinhard
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Fossil pollen and paleoclimatology

Eos, Transactions American Geophysical Union, 1949
Pollen analysis has been extensively used in Europe not only in studies of postglacial climatic fluctuations, but also in conjunction with investigations of eustatic changes in sea level and isostatc land movements. A beginning in this field of research has been made in several sections of the United States.
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Pollens fossiles d'Euphorbiacées de l'Eocène français

Grana, 1992
Abstract Pour la premiere fois des pollens des genres Actephila, Reverchonia et Bischofia sont signales a l'etat fossile a l'Eocene. Ils sont decrits dans ce travail avec ceux de Drypetes, Mallotus, Phyllanthus et Ricinus. Du point de vue paleophytogeographique la decouverte dans l'Eocene moyen de Bischofia, genre actuellement asiatique et ...
Carla Gruas-Cavagnetto, Egon Köhler
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Evolutionary trends in fossil gymnosperm pollen

Review of Palaeobotany and Palynology, 1976
Abstract The evolution of cordaite, conifer, and cycadophyte pollen types are discussed relative to germination polarity, external ornamentation, suture organization, saccuscorpus development, and sporoderm ultrastructure. Information is presented in which the development of the microgametophyte is considered together with an analysis of the ...
M.A. Millay, T.N. Taylor
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Fossil pollen records of extant angiosperms

The Botanical Review, 1981
The fossil record for angiosperm pollen types which are comparable to recent taxa is evaluated, following a similar survey published in 1970. Special attention is paid to the dating of the sediments. Evidence for 139 families is considered to be reliable, for others the records are cited as provisional, pending the accumulation of more evidence.
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Fossil Pollen in Scottish Jurassic Coal

Nature, 1937
I HAVE recently made an examination of the microspore content of a sample of coal of Jurassic age that occurs at Brora, Sutherlandshire. The seam rests upon strata of the Estuarine Series (g7), and has as its roof-bed Kellaways Rock (g10). The seam proves to have a rich content of pollen, principally of genera of conifers belonging to the Abietineae ...
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Reappraisal of some subsaccate fossil pollen genera

Journal of Palaeosciences, 1968
Tsugaepollenites (Potoni6 & Venitz) Potonie 1958, Cerebropollenites (Nilsson) emend. and Triangulbpsis (Doring) emend. have been morphographically studied in this paper. Cerebropollenites and Triangulopsis which were formerly grouped under Tsugaepollenites by Dettmann (1963) have been excluded from its limits and evidence has been adduced for this ...
H.P. Singh, Pramod Kumar
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Fossil Nothofagus Pollen

Ecology, 1940
Stanley A Cain, L. M. Cranwell
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