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On the occasion of the opening of the Second International Conference on Palynology, celebrating the fiftieth anniversary of modern palynology, some memories are reported of Lennart von Post and the pioneer stage of pollen analysis. A critical note is made about the often too uncritical description and naming of pre-Quaternary pollen and spore taxa. Pollen grains indistinguishable from those of Artemisia norvegica , a plant of great phytogeographical significance, in Scandinavia now only found in a well-circumscribed area in Norway, have recently been identified from a pre-Late Quaternary deposit in central Sweden. Work on a “World Pollen Flora” has started.

RIASSUNTO Le caratteristiche morfologiche del polline possono fornirci argomenti per trasferire il genere Berenice dalle Saxifragaceae alle Campanulaceae e per mantenere Pentadiplandra (Fig. 5) nelle Capparidaceae. I granuli pollinici nelle Chlaenaceae (Fig. 1–3) sono uniti in tetradi. Queste sono usualmente omodinamosporee (i 4 granuli pollinici sono della medesima grandezza); in alcune specie esse sono eterodinamosporee (i 4 granuli pollinici non sono tutti della medesima grandezza; cf. Fig. 1 B). Tetradi eterodinamosporee si riscontrano anche in alcune specie di Epacridaceae ed Ericaceae. Dioncophyllum (Fig. 4) differisce per la morfologia del polline dal resto delle Flacourtiaceae; Choristylis e strettamente imparentato con Itea. Le specie sudamericane di Macrolobium possono essere distinte dalle specie africane per mezzo delle caratteristiche morfologiche del polline. D'altro lato non vi e una differenza apparente tra i granuli pollinici di Gilbertiodendron e Pellegriniodendron e quelli delle specie ...

Tricolpate pollen grains, described in the present paper under the name Tricolpites (Eucommiidites) Troedssonii nova sporomorpha, occur regularly in the early Jurassic shale at Palsjo in northwestern Seania. Grains or spores of this particular type have only been met with among dicotyledonous plants. They do not, according to our present knowledge, occur in recent and fossil monocotyledons, chlamydosperms, gymnosperms, ferns, or mosses.

(1961). Cormophyte Spore Classification. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 83, No. 1, pp. 65-78.

Four phenomena were observed in a study of Populus tremula and P. tremula f. gigas microspores from before microspore mitosis through mature pollen which may have general significance in the ontogeny of pollen grains: 1) The exine and orbicules (Ubisch bodies) were covered by membranes. 2) The exine and the tapetal surfaces where orbicules form were covered by a polysaccharide (PAS positive) coat until after microspore mitosis; subsequently the tapetum became plasmodial. 3) Material having the staining characteristics of the nexine 2 (endexine in the sense of Faegri) accumulated on membranes in microspores in the space between the exine and the plasma membrane. That material was almost completely gone from the wall in mature pollen. The membranes on which material had accumulated migrated through the exine. Following passage through the exine these membranes were seen as empty fusiform vesicles in micrographs of anthers prepared by commonly used methods. 4) At about microspore mitosis when the cel...

Examination of the pollen morphology, floral morphology and anatomy, and vegetative anatomy of Emblingia calceoliftora F.Muell.leads to widely divergent views concerning its systematic affinities. Erdtman considers that pollen morphology shows Emblingia should be referred to, or near to, Polygalaceae; the pollen grains are unlike those of Capparaceae, Goodeniaceae or Sapindaceae. Leins concludes that Emblingia is probably allied to the Sapindaceae. He lists the following similarities: three-carpellate, septate ovary with one axile ovule in each loculus; short androgynophore; eccentric, extrastaminal disk; reductions in corolla and androecium; ventral appendages to petals; spiral embryo and aril; bitegmic and crassinucellate ovules. Melville interprets the hood of the androgynophore of Emblingia as a third petal and the gland (‘disc’) as a reduced stamen fascicle; the floral parts show a tendency to adhesion such as is common in the Goodeniaceae.Emblingia resembles Scaevola in general habit and hair type; the trimerous ovary, stigmatic vascular brush, and reniform seeds with curved embryos and complex vascular supply also suggest an affinity with Goodeniaceae. Metcalfe's examination of the leaf and stem anatomy of Emblingia shows that the histological resemblance is closest to Goodeniaceae and next closest to Polygalaceae. Similarities to Goodeniaceae include minutely warty, unicellular hairs; branched sclereids; vascular bundles of leaf sheathed by inflated parenchymatous cells; deep-seated origin of cork in stem; xylem forming a closed cylinder in stem, traversed by narrow rays; mostly solitary vessels with simple perforations.

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The idea of an affinity between Aquilapollenites and the Loranthaceae published some years ago (Erdtman, 1963, p. 157) is dealt with in greater detail and with due consideration of new data presented by Srivastava & Rouse (1970). Appended is a note on the relationships—if any—between Gnetum and certain Loranthaceous taxa

Table I shows that two letters (S, N) and two figures (1, 2) can be used as symbols or “labels” instead of more or less complicated and/or ambiguous terms in labelling the main topographical and/or non-topographical sub-units or parts of angiosperm exine types (at least as far as present knowledge goes). Special attention has been paid to the characteristics of the nexine in Epilobium montanum believed to be “nexine-2” (N2) by Erdtman and others, albeit classified as “nexine-1, footlayer of the ektexine” by Rowley et al. (1970; p. 7).

Partial decay of the exine in pollen grains of Epilobium and Geranium in mineral soils is described. An example is provided of exine corrosion, probably due to microbial activity, in birch pollen. Suggestions are made concerning “interbedded zones” in the nexine of Cobaea and Passiflora . Bacular conditions at or near the transition from the sexine to the nexine need more study. Cf. “stalactites”, “ordinary (infratectal) bacules”, and “quasi-ordinary bacules” provided (at least temporarily) with a distinct, root-like extension into the nexine etc. In conclusion it may be asked, if we - by altering, in one way or another, the “natural physiology of pollen development” - are able to get further insight into the mechanisms of still enigmatic morphogenetic etc. processes.

(1952). Pollen Morphology and Plant Taxonomy. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 74, No. 4, pp. 526-527.

IN Late-Quaternary deposits in England, pollen grains of Tilia have their maximum frequency, as a rule, in strata formed during the Post-Glacial climatic optimum. This fact was reported many years ago1, and has been amply confirmed by later investigations. To the finds of Tilia pollen made hitherto (exclusively finds of T. cordata2) can now be added the finding by one of us (J. P. T. B.) of peat at Addington, Kent, the pollen flora of which was later investigated by Erdtman and found to contain—in its basal portions—pollen grains of Tilia platyphyllos. This peat bed seals an occupation site of Mesolithic age characterized by axes, gravers and microliths.