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In the system of classification sensu Cronquist, the division between the two subclasses Dilleniidae and Rosidae relies on only a few characters. The major distinguishing character is the occurrence of centripetal or centrifugal sequence of stamen development. We question not only the application and the value of this character, but also the maintenance of the Rosidae and Dilleniidae as separately derived natural taxa, because of the lack of solid distinguishing criteria. We have studied the staminal characters in the 192 families of the Dilleniidae and the Rosidae, using Dahlgren's classification diagram. The study focussed on the following androecial characters: 1) polyandry; i.e. spiral polyandry, complex polyandry (viz. centrifugal, centripetal and lateral polyandry) and cyclic polyandry 2) diplostemony and obdiplostemony 3) haplostemony and obhaplostemony. In our proposal only two characters are maintained, namely oligomery (diplostemony s.l.) and polymery (true polyandry s.l.), both having a number of character states. Polyandry, as it has been described up to now, is not to be regarded as homologous in all Magnoliophytina. Both characters correspond to two different lines within the Magnoliatae. In addition, the division between the Dilleniidae and Rosidae sensu Cronquist is no longer tenable. Finally, a number of modifications of Dahlgren's diagram are suggested and a division of the Magnoliophytina in a polymerous group and an oligomerous group is proposed. The Dilleniidae-Rosidae complex is included in the oligomerous group.

The genus Fuirena Rottb. is currently classified in the tribe Fuireneae Reichenbach ex Fenzl (subfamily Cyperoideae), based on the presence of spikelets with many spirally arranged glumes, each subtending a bisexual flower, and because of unique embryo characters. The trimerous Fuirena flowers have two whorls of perianth parts that show a wide morphological variety and various reduction trends. In flowers of F. ciliaris (L.) Roxb., the outer whorl consists of three bristle-like perianth parts opposite the stamens. The three scale-like inner perianth parts alternate with the stamens. The nature and exact position of the inner perianth parts have long been a subject for discussion. In the context of the 'synanthium' hypothesis, some authors have interpreted the perianth parts as floral bracts. Alternatively, the inner perianth parts have also been interpreted as staminodia because of their appearance and position. In this study we present new evidence in favour of a conventional monocotyledonous pentacyclic flower model in Cyperoideae based on SEM observations on the floral ontogeny of F. ciliaris, F. leptostachya Oliver, F. abnormalis C.B.Clarke and F. pubescens (Poir.) Kunth. Our observations confirm a pentacyclic organisation of the flowers within Fuirena, and they corroborate the interpretation of the inner scales and outer bristles as perianth parts.

Pyrene and pollen morphology of several neo- and paleotropical Geophila species is documented and discussed. Pyrenes show distinct morphological variation. They have one central or several adaxial ribs and are straight or twisted. Neotropical species only have twisted pyrenes, whereas Madagascan species have straight ones. Both pyrene types occur on the tropical African mainland and in tropical Asia. The genus is eurypalynous, including inaperturate, colpate and pantoporate pollen. The paper includes the first record of operculate pollen in the Rubiaceae, viz. in Geophila repens var. repens. Pyrenes as well as pollen morphology indicate that the varieties of the pantropical species G. repens need recognition at the specific level.

Pollen diagrams from mountain lakes and marshes in SW Turkey show evidence of intensive anthro pogenic influence in the landscape between 3500 and 1300 BP. Three cores from within the territory of the classical city Sagalassos (Western Taurus, Pisidia) were palynologically analysed to make a reconstruction of the past vegetation in the territory of Sagalassos and to estimate the impact of its inhabitants on the landscape in Pisidia. Two cores originate from an intramontane marsh (Gravgaz; elevation 1215 m) and one from a seasonal intramontane lake (ÇanaklK; elevation 1030 m). Human acitivity is apparent from c. 2530 BP in the pollen diagrams. A deforestation phase/‘disturbance’ phase (from c. 2530 BP/c. 2480 BP till c. 2280 BP/c. 2270 BP), anthropogenically or climatologically driven, precedes a cultivation period (arboricultural phase) (from c. 2280 BP/2270 BP till c. 1480 BP/c. 1270 BP). The results of the pollen analyses of the three cores are compared and show many similarities. There are also similarities with other cores from SW Turkey, although the arboricultural phase (mainly olive cultivation) occurs later in the cores from the Sagalassos territory than in other cores from SW Turkey.

The pollen morphology and distribution of orbicules were investigated in ten species of the genus Coptosapelta (Rubiaceae) using light, scanning electron and transmission electron microscopy. In general, Coptosapelta pollen is three- to five-pororate and suboblate to oblate-spheroidal. The sexine ornamentation varies from psilate to reticulate, and the pollen-wall stratification lacks columellae. 'Droplets' are observed on the inner nexine surface. Distinct orbicules are found in five species. Orbicules are often lobed and appear to be aggregated and embedded in the tapetal remnants of the locule wall. Ultrastructurally, a single, flattened core is frequently observed. Coptosapelta has a unique pollen type within Rubiaceae and does not resemble possibly related genera. Pollen characteristics provide additional evidence supporting earlier findings that Coptosapelta represents an isolated lineage in Rubiaceae.

Two travertine sections in the valley of Baskoy, near the archaeological site of Sagalassos have been palynologically investigated. The base of one of these sections has been dated to 9000±600 yr B.P. by the U/Th dating technique. The pollen diagrams of both sections reveal the importance of deciduous Quercus and Betula woodlands during deposition of the travertine. The development of woodlands in the early Holocene implies an increase in humidity after the Late Pleistocene. An annual precipitation of at least 500 mm/yr is suggested. A study of the δ18O values of the travertines in the sections indicates a change to higher precipitation temperatures of the travertines and hence a climatic change to higher air temperatures around 9000±600 yr B.P. This increase in temperature is not documented in the pollen diagrams. The evaluation of the local pollen curves provides additional information on the depositional environment. The facies and pollen analyses indicate that the travertines were deposited in a fluvial–barrage system. High abundances of Cyperaceae pollen suggest a marshy environment and fluctuating water levels of this early Holocene fluvial-barrage system. High percentages of Poaceae and/or Aster and Mentha–Thymus pollen types point to drier local conditions at the beginning and the end of the travertine accumulation of both sections.

The floral ontogeny of four species of Phytolacca (P. acinosa, P. clavigera, P. dodecandra, and P. americana) shows major differences in the number and position of stamens and carpels. Five sepals are always formed in a 2/5 sequence. The number of stamens is mostly eight, with a sequential initiation: six outer stamens are arranged in three pairs opposite sepals 1-3; single stamens stand opposite sepals 4-5, except for P. americana, where all antesepalous stamens are positioned in pairs (10 stamens rather than eight). The stamens of the first, second, and third pair arise simultaneously as independent entities. The stamens of the third pair occasionally arise sequentially and are displaced in relation to the third sepal. Stamens opposite sepals 4 and 5 follow sequentially. The delayed plastochron of the stamens opposite sepal 3 indicates that the pentamerous flower has been derived from a trimerous precursor. Phytolacca dodecandra has 10 stamens arising in a different sequence: the five inner stamens are ...