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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 ...

Geologie regionale Hogbom, A. G., Sveriges jord och grund. (The earth and ground of Sweden.) 230 pp. Lindblads forlag, Uppsala, 1927. Jessen, Knud, Det forhistoriska Europas naturforhallanden. (Die Naturverhaltnisse des vorgeschichtlich e n E u r o p a s.) 57 S. 18 Textfig. (Aus: De forhistoriska tiderna i Europa I, Stockholm 1927). Munthe, Henk., Hede, J. Ernhold och Lundqvist, G., Beskrivning till kartbladet Klintehamn. (Beschreibung zum Kartenblatte Klintehamn.) Sv. Geol. Unders. Ser. Aa. N:o 160. S. 1–109. Stockholm 1927. Munthe, H., Hede, J. E., och von Post, L., Beskrivning till kartbladet Hemse. (Beschreibung zum Kartenblatt e H e m s e.) Sv. Geol. Unders. Ser. Aa. N:o 164, 155 S., 93 Fig., 2 Karten, Stockholm 1927. von Post, L., Beskrivning till Oversiktskarta over sodra Sveriges myrmarker. (Beschreibung zur Ubersichtskarte uber die Moore Sudschwedens.) — Sv. Geol. Unders., Ser. Ba. N:o 11. Stockholm 1927. Sandegren, R., Beskrivning till kartbladet Luro. (Beschreibung zum Kartenblatte Luro.) — Sv....

(1930). Literature on Pollen-statisties published during the years 1927–1929. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 52, No. 2, pp. 191-213.

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.

(1927). Literature on Pollen-statistics published before 1927. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 49, No. 2, pp. 196-211.

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

(1955). Literature on Palynology. XVIII. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 77, No. 1, pp. 71-113.

(1944). Literature on pollen-statistics and related topics published 1940—1943. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 66, No. 2, pp. 256-276.

(1928). Studies in the postarctic history of the forests of Northwestern Europe. I. Investigations in the British Isles. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 50, No. 2, pp. 123-192.

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.