SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Seed anatomy and pollen morphology support the transference of the Australian Streptothamnus beckleri to the Chilean genus Berberidopsis.

Floral morphology of Stemonaceae and Pentastemonaceae

Ano: 1984

URL: http://www.repository.naturalis.nl/record/525061

The early development of the stamens in Stemona and Stichoneuron is similar, in spite of significant differences in the adult stages. Moreover, as the peculiar gynoecia in both genera are chiefly similar, their mutual affinity seems substantiated. It is concluded that Stichoneuron is very close to Croomia, so that these genera can be merged. However, Pentastemona is different. In its androecium it shows a corona-like development of the basal staminal region (like Peliosanthes, Convallariaceae). Therefore, the removal of Pentastemona from the Stemonaceae is corroborated. The late differentiation of its stamens into extensions that contact the stigma, as well as the inferior position of the ovary, suggest a relationship with Trichopus (Trichopodaceae) and...

Flowers and fruits in Flacourtiaceae. I. Scaphocalyx spathacea Ridl

Ano: 1992

URL: http://www.repository.naturalis.nl/record/525493

Descriptions are given of the flowers, fruits, and seeds. The petals have basal scales. The pistil is an urceolate structure issuing in 5—7 stigmas. In it are two whorls of ovules along the wall, the lower whorl in the same radial planes as are the stigmas, the upper whorl in alternate radii. The pistil wall is entirely covered by nectariferous hairs. There is a peculiar vascular bundle pattern. The ovule is sessile and atropous, the nucellus is beaked, the inner integument terminates into 2—4 projections, the outer integument into 2—4 lobes. The ovules develop into inferior seeds mainly by proximal growth. Lobes of the endocarp grow around the ectostome. The testa has its hard layer in the middle. The seeds consist of two parts, a hard container...

Variation in the development of ascidiform carpels, an S.E.M.-investigation

Ano: 1973

URL: http://www.repository.naturalis.nl/record/526037

Attention is drawn to the differences in place and time of origin of the abaxial (upper) and adaxial (lower) parts of the margin of ascidiform carpel primordia. It is assumed that the adaxial parts will develop more fully when the primordia have more space and time to develop on an expanding floral apex. The favoured occurrence of the margin at the base of the primordia seems a prerequisite to incipient syncarpy.

A S.E.M.-investigation on the development of free carpels

Ano: 1984

URL: http://www.repository.naturalis.nl/record/525626

The early development (ontogeny) of the carpels of 20 species belonging to 8 apocarpous families was investigated with the scanning electron microscope. The results indicate that on the floral apex a circular or a convex meristem develops into an obliquely ascidiate primordium by unequal growth of its periphery. By further unequal growth it develops into a young carpel. The terminal mouth of a cup becomes the lateral cleft of a carpel. The different forms of the young carpels in different species are defined by the varying degree of development of the adaxial region of the initial meristem and/or its margin on the side of the floral apex. This hypothesis is theoretically evaluated.

The pattern of vascular bundles in the stamens of Nymphaea lotus L. and its bearing on stamen morphology

Ano: 1981

URL: http://www.repository.naturalis.nl/record/525801

In 1969 I published, together with P. G. Heinsbroek, a paper on the anatomy of the stamens of Victoria amazonica. The flowers used in that study came from plants which were cultivated in the green-house of the Leiden Botanic Garden. Because the possibility could not be excluded that the structures then observed were partly the effect of greenhouse conditions, I subsequently took the opportunity to study flowers of well developed plants, which were cultivated in the open air under the tropical conditions of the Botanic Garden at Bogor*). The results were exactly the same. Apart from the set of central vascular bundles, normal in laminar structures, there proved to be a peripheral sheath of bundles consisting of abaxial bundles, terminating half way up the...

The early development of inflorescences and flowers of the oil palm (Elaeis guineensis Jacq.) seen through the scanning electron microscope

Ano: 1977

URL: http://www.repository.naturalis.nl/record/524678

Heel, W.A. van; Breure, C.J.; Menendez, T..

The development of inflorescences and flowers of the African Oil Palm up to anthesis is illustrated by scanning electron microscopy images. The time of origin relative to the development of the foliage leaves of the basipetalous succession of flowering rachillae is determined, as well as the time of morphological sex definition. The logical stage when sex is determined is inferred to be not before the first appearance of the spikelet primordia. Female flower groups develop acropetally as triaxial cincinni, the male units as reduced ones. A developmental diagram is added.

The pistil of Bertolonia marmorata Naud. (Melastomataceae)

Ano: 1987

URL: http://www.repository.naturalis.nl/record/524903

The flower of Bertolonia marmorata, a small herbaceous plant from South Brazil, is epigynous, pentamerous except for the trimerous gynaecium, pentacyclic and diplostemonous. The ovary is fused to the perianth-tube basally, on cross-section it appears as an equilateral triangle, one corner of which is taken by a locule situated abaxially and epipetalous. The style is terminal, and the stigma simple, but around the style the walls of the ovary, especially their middle parts, extend freely upwards (Fig. 13). The axillary placenta is an awl-formed structure, projecting into the locule rather perpendicular to the pistil axis.

Morphology at the Rijksherbarium

Ano: 1958

URL: http://www.repository.naturalis.nl/record/526377

In the following the role of morphology, anatomy and palynology in systematics at the Rijksherbarium will be discussed, as far as flowering plants are concerned. It will be demonstrated that most of the research in this field is rooted in the interest of individual workers, and that no planning was involved until recently. The scope of it varied, as it was done either for pure taxonomic purposes, or for systematic and phylogenetic reasons, or for its own merit. Chiefly, I think, the study of morphology s.l. originated because Suringar, Hallier, Lotsy, and especially Lam, were interested in achieving a more natural or evolutionary system of the Angiosperms. Lotsy and Lam extended their interest to the other Cormophytes as well. In 1895 W. F. R. Suringar...

Note on the early development of the integument in some Juglandaceae together with some general questions on the structure of Angiosperm ovules

Ano: 1979

URL: http://www.repository.naturalis.nl/record/524558

Heel, W.A. van; Bouman, F..

Recently a review on the Angiosperm ovule has been published by the well-known Indian botanist V. Puri (1970). In this review the author stressed the differences between Angiospermous and Gymnospermous ovules, and he refused to accept their comparability or common descent. In this respect Puri comes close to Eames (1961). Both authors tend to regard the ovules as complex emergences. Apart from the main theme, there is a striking passage in this review dealing with the Hugo de Vries Laboratory at Amsterdam. According to Puri in that laboratory facts are sacrificed for hypotheses (p. 10). In the following we would like to start with the facts concerned and present them in a more convincing way, and then ask some simple questions on the structure of the...

Anatomical and ontogenetic investigations on the morphology of the flowers and the fruit of Scyphostegia borneensis Stapf (Scyphostegiaceae)

Ano: 1972

URL: http://www.repository.naturalis.nl/record/525600

New details could be derived from the study of fixed male and female flowers of Scyphostegia borneensis Stapf. Of prime importance among these is the exact structure of the female reproductive units. They correspond to what are generally recognized as ovules. These anatropous ovules have a constriction separating funicle and raphe, an aril (loid) of mixed character, a distal integumental extension, and a fivelobed exostome. Their placentation is basal. Together, they are enclosed by an urceolate wall consisting of three-trace units which are apically stigmatic. These sterile units form septs growing downwards between the tips of the ovules, giving rise to locules which are open below. The morphological interest of some of these details was discussed. The...

Ano: 1967

URL: http://www.repository.naturalis.nl/record/525292

Reviews

Vink, W.; Leenhouts, P.W.; Balgooy, M.M.J. van; Hovenkamp, P.; Vermeulen, J.J.; Wilde, W.J.J.O. de; Heel, W.A. van.

The Hamameli(i)dae comprise, according to the new classification by Thorne, about one quarter of the genera to one third of the families of the Dicotyledonae. The symposium held at the University of Reading, U.K, 22-25 March 1988, highlighted some of the many questions concerning phylogeny and evolution in this group as a contribution to the insight in the main lines of dicotyledonous evolution. The symposium report contains a wealth of information on a wide variety of topics. The phylogenetic position of the Hamamelidae in a wider or narrower sense, or parts thereof, is subject of a number of papers. F. EHRENDORFER reviews the existing diverging interpretations and concludes that the Hamamelidae can be regarded as ancient and partly relictual survivors...

Note on the morphology of the male inflorescences in Cercidiphyllum (Cercidiphyllaceae)

Ano: 1990

URL: http://www.repository.naturalis.nl/record/525453

Male reproductive axes are described which have three pairs of decussate bracts, some with free axillary groups of stamens. The developmental stages are demonstrated by scanning electron microscopy (SEM). The view, earlier advanced for the female counterparts, that these reproductive axes are reduced polyaxial systems, is supported.

Ano: 1987

URL: http://www.repository.naturalis.nl/record/524939

Review

This book is an exploration into the field of Plant Morphology. It deals with the placentation of the ovules in ten families of Centrospermae — including the Cactaceae — and in the Primulaceae. The core is formed by a very close observation and a complete documentation of the histogenesis of the ovary wall, the septs, and the placentae in four Caryophyllaceous species. Furthermore, the result is compared with similar known and newly discovered features in other species and in the other families. It appears that the ovary is composed of a cup of sterile phyllomes which surrounds a central body. This central part is built up by two alternating sets of five axial placentae bearing the ovules. The septs grow from the cup inwards and fuse with the placentae and...