Development of ovules of Illicium anisatum (Illiciaceae), Trimenia moorei (Trimeniaceae), and Austrobaileya scandens (Austrobaileyaceae) (Austrobaileyales) was observed. In Austrobaileya scandens and Trimenia moorei the outer integument is hood-shaped, while it is cup-shaped in Illicium anisatum. On the basis of a phylogeny, the ovule with the hood-shaped outer integument is suggested to be primitive in Austrobaileyales. Seed development of Austrobaileyales was also examined. In Austrobaileya scandens the seed is mesotestal, ruminated, not pachychalazal, and has a micropyle-hilum complex. In Trimenia moorei the seed is exotestal, perispermous, not pachychalazal, and has a micropyle-hilum complex and a circular cap. The seed of Illicium anisatum is exotestal, not pachychalazal, and has a circular cap. Taking the character states of other basal angiosperms into account, primitive seeds of angiosperms are inferred to have such characters as the unilayered exotestal mechanical tissue, circular cap, micropyle-hilum complex and non-pachychalazy. The inferred primitive seed is very simple, suggesting that a great diversity of seeds is established through elaboration of organs/tissues of seeds, and not through reduction as hypothesised previously. B T 0 3 0 5 6 O v u l e s a n d s e e d s o f Au s t r o b a i l e y a l e s T . Y a m a d a e t a l .

Austrobaileyales, comprising the four families Austrobaileyaceae, Trimeniaceae, Schisandraceae, and Illiciaceae, are included in the basal angiosperms along with Amborellaceae and Nymphaeaceae. Here, we present the first developmental study of the female gametophyte in Austrobaileya scandens, the only species of Austrobaileyaceae, which are sister to the rest of the Austrobaileyales. Austrobaileya scandens has a four-celled/four-nucleate embryo sac as in the derived families of the order, e.g., Illiciaceae and Schisandraceae. It is monosporic, with the chalazal megaspore of a tetrad developing into the embryo sac composed of an egg cell, two synergids, and one polar nucleus. This mode of embryo sac formation was first reported in Schisandra over 40 years ago and should now be established as the Schisandra type. Its occurrence in A. scandens shows that the Schisandra-type embryo sac is likely common to the whole Austrobaileyales as well as to Nymphaeaceae. Amborellaceae were recently reported to have an eight-celled/nine-nucleate embryo sac, clarifying that none of the basal angiosperms has the seven-celled/eight-nucleate Polygonum-type embryo sac found in the majority of angiosperms, and that the Polygonum-type embryo sac represents a derived character state in angiosperms.

The structure of the anther and ovule and the development of the male and female gametophytes have been studied in seven cultivated varieties of Capsicum-C. annuum L. var. acuminatum Fingerh. (long red cayenne), C. annuum L. cv. Floral Gem, C. annuum L, var. grossum (L.) Sendt. (giant bell), C. annuum var. longum (DC.) Sendt. (long sweet yellow), C. baccatum L. var. pendulum (Willd.) Eshbaugh, C. frutescens L, var. baccatum (L.) Irish and C. frutescens L, cv. Tabasco. Marked differences in the development were observed between flower buds formed in summer and in winter. In the anthers of winter flower buds of C. annuum var, acuminatum the pollen grains show nuclear multiplication and pollens with all nuclear numbers between two and eight are represented. However, 'pollen embryo sacs' as such are not formed. The normal viable pollen grains are binucleate. The pollen fertility in summer is 93.6% while in winter, on the same plants, it is only 31.3 %. In the development of the ovule there are no marked differences amongst the varieties except in size. Coexistence of mono-, bi- and tetrasporic embryo sac developments has been found in C. annuum var. acuminatum in which monospory is dominant in summer but bispory in winter. Monosporic and bisporic embryo sacs coexist in C. baccatum var. pendulum and C. frutescens var. baccatum. The other varieties show only monosporic development.

An embryological study of Piper methysticum Forster f. (Piperaceae), undertaken to identify the probable cause for the absence of fruits in cultivated varieties, has revealed that the majority of plants in all the cultivars examined bore only male flowers. The anthers are tetrasporangiate and the anther wall comprises a well-developed endothecium with fibrous thickenings, two middle layers and a glandular tapetum. Meiosis is normal and simultaneous cytokinesis leads to tetrahedral microspore tetrads. Pollen degeneration was observed but was of very rare occurrence. The pollen grains are released when they are 2-celled and appear to be healthy and capable of germination. The unilocular ovary contains a single basal ovule which is orthotropous, bitegmic, and crassinucellar. Both integuments contribute to the formation of the micropyle. The development of the female gametophyte conforms to the tetrasporic Fritillaria-type. No abnormalities were noticed either in meiosis of the megaspore mother cell or in subsequent development leading to the formation of the mature embryo sac. Occasional parthenocarpy was observed but without viable seeds being present inside. It is suggested that, although the lack of fruit formation in this species is not because of any deficiencies in its embryological development, it may be due to a simple self-incompatibility mechanism.

Pollination was studied in three species of Araucaria: A. cunninghamii, A. heterophylla and A. bidwillii. More limited observations were made for A. hunsteinii and A. angustifolia. The investigation revealed considerable variation among species of Araucaria with respect to pollination features. The bract scale of the receptive cone of both A. cunninghamii and A. heterophylla has a stoma-free furrow which directs pollen grains onto a thin flange on the tip of the ovuliferous scale. The bract scale of A. bidwillii bears stomata over most of its surface, and is broadly scalloped so that pollen grains are deposited in a band across both bract and ovuliferous scales. On germination, the pollen tubes of these three species penetrate the epidermis of the scale and for a short distance grow beneath the surface before emerging and travelling, without branching or major deviation, towards the proximal end of the ovuliferous scale. On reaching the micropyle, the pollen tubes enter the nucellus. In known features, pollination in A. hunsteinii resembles that in A. bidwillii. The pollen tubes of A. Angustifolia bear short branches and, in distal regions of the scale, are erratic in their orientation. Results are discussed in relation to pollination mechanisms in other conifers and to taxonomic divisions within the Araucariaceae.