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

In one ‘flower’ a growing point occurred between a bract and its seemingly inverted carpel.

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

Ano: 1986

URL: http://www.repository.naturalis.nl/record/524974

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.

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

Ano: 1981

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

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...

Distally lobed integuments in some Angiosperm ovules

Ano: 1967

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

In this treatise ‘De l’Ovule’ Warming (1878) remarked that although the borders of the integuments grow uniformly, very rarely a division into lobes can be observed. He mentioned Symplocarpus foetida (inner integument four-lobed), Lagarosiphon schweinfurthii (outer integument four- or five-lobed) and Juglans regia (two-lobed). Moreover he cited the report by some authors of an occasional occurrence of lobed integuments in a few more plants. More recently Leroy (1955) described bilobed single integuments in Juglans and Platycarya. Boesewinkel and Bouman (1967) demonstrated that these lobes arise as two separate primordia in Pterocarya and Juglans.

Floral morphology of Stemonaceae and Pentastemonaceae

Ano: 1970

URL: http://www.repository.naturalis.nl/record/525594

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...

Flowers and fruits in Flacourtiaceae. II. The seeds of Pangium edule Reinw

Ano: 1973

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

The seeds are inferior. Only in the apical part of the seed the testa is integumental; for the greater part it is chalazal. A thick mesotesta is formed by a matted layer of sclereids. The chalazal part of the ectotesta is richly vascularized. A sheath of inverted vascular bundles occurs on the inside of the chalazal part of the mesotesta. The seeds are albuminous, the cotyledons foliaceous. An inside cavity may make the seeds float in water. The nucellar beak persists in the ripe seed. The endopyle is five-rayed in c.s., the ectopyle is a longitudinal slit.

Flowers and fruits in Flacourtiaceae. III. Some Oncobeae

Ano: 1974

URL: http://www.repository.naturalis.nl/record/524602

Data are presented on Oncoba, Caloncoba, Camptostylus, Dasylepis, Scottellia, Berberidopsis, Lindackeria, and Peterodendron, with special emphasis on development and anatomy of the gynoecium. A neutral view is preferred to the carpel theory. There appears to be a link between parietal and basal placentation. It is proposed to refer to this placentation as cupular. Several peculiarities are found, such as ‘ramification’ of the stigmatic canals, penetration of the embryosac into the chalaza, distal lobes on integuments, separate vascular traces to the lowermost ovules, etc.

Flowers and fruits in Flacourtiaceae. IV. Hydnocarpus spp., Kiggelaria africana L., Casearia spp., Berberidopsis corallina Hook. F

Ano: 1977

URL: http://www.repository.naturalis.nl/record/524458

In Hydnocarpus the hard layers of the seed coat develop from the epidermides of both integuments where they are contiguous. This does not conform with the division of the Angiosperm seeds into testal or tegmic. Corner’s suggestion of two unallied groups in the Flacourtiaceae, namely an integumental and a pachychalazal one, cannot be corroborated. The seeds of Kiggelaria closely resemble those of Hydnocarpus. In Casearia the development of the fruit wall and its vascular bundles is different for the Asian and the American species studied. The three parietal placentae are confluent over the base of the ovary. The seeds are exotegmic, as described by Corner; the ovules are atropous. The berries and seeds of Berberidopsis are described for the first time. The...

Flowers and fruits in Flacourtiaceae. V. The seed anatomy and pollen morphology of Berberidopsis and Streptothamnus

Ano: 1979

URL: http://www.repository.naturalis.nl/record/525775

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

Morphology at the Rijksherbarium

Ano: 1984

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

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...

Morphology of the androecium in Malvales

Ano: 1979

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

In order to test the applicability of the telome and the classic theories to the nature of stamens a study was made of flowers in Malvaceae, Bombacaceae, Sterculiaceae, Tiliaceae, and Elaeocarpaceae with respect to their ultimate form, their development, and the vascular course of their androecia. The customary dissecting, clearing, and microtomy techniques were used. A chapter on the interpretation of the vascular bundle course in floral morphology has been added. In each flower the stamens are considered to be arranged in five groups, which may be fused more or less laterally. The groups have a three-trace vascular system the laterals of which may be commissural. Only a few Tiliaceae have ten groups. Whereas in most Tiliaceae and Elaeocarpaceae the...

Morphology of the pistil in Malvaceae-Ureneae

Ano: 1966

URL: http://www.repository.naturalis.nl/record/524954

The puzzling fact that the pistils of Malvaceae-Ureneae have five locules, but ten, instead of five, stylar branches, is made clear by a study of their development.

Note on some more tropical labyrinth-seeds

Ano: 1978

URL: http://www.repository.naturalis.nl/record/525944

There are seeds that, when cut in any plane, show a labyrinth structure (van Heel, 1970). This may be due to folding of the cotyledons (Burseraceae, Dipterocarpaceae), or to the presence of testa tissue within the seed. In the latter case the testa tissue may either be located in the endosperm only (‘ruminated seeds’ in Palmae, Annonaceae, etc.), or the testa tissue may interfere with the cotyledons. It is possible that in some cases the testa at first interferes with the endosperm, and later on, when the embryo has become larger, also interferes with the cotyledons (Corner, 1966, in some Palmae). In the case of testa tissue interfering with the cotyledons, there are probably two possibilities. Firstly the testa may be located between portions of folded...

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

Ano: 1971

URL: http://www.repository.naturalis.nl/record/524652

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...

Note on the floral development of Thottea (Aristolochiaceae)

Ano: 1972

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

Leins, P.; Erbar, C.; Heel, W.A. van.

The occurrence of four placentae is a constant character in Thottea. The species can be distinguished by differences in the androecium. The androecial pattern is relatively variable and its rather high plasticity in the genus is suggested to be a derived feature within the family. The gynoecial structure is most remarkable, as the stylar organs do not correspond with the placentae in number nor in position. It is assumed that these organs do not belong to the gynoecium morphologically. They may represent independent, phylogenetically secondary organs, which may function in the capturing of pollen.

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

Ano: 1988

URL: http://www.repository.naturalis.nl/record/525710

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.

Note on the structure of developing seeds of Knema and Horsfieldia (Myristicaceae)

Ano: 1987

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

The structure of the seed is based on the massive development of the ovule immediately above the insertion of the outer integument. This may be called endochalazal development, as suggested by F. Bouman (Pers. comm.).

On the development of some Gynoecia with septal nectaries

Ano: 1982

URL: http://www.repository.naturalis.nl/record/526141

Septal nectaries are formed by local regions of later nectariferous epidermal cells on the sides of the carpels at their very base. In order that the epidermal cells may differentiate into nectariferous cells, the carpels which constitute the gynoecium have to develop as separate organs. It was argued that if no septal nectaries develop, this free carpel development does not take place. The nectariferous regions get shaped as nectar containers by dermal fusion of the sides of the carpels surrounding them, by upward growth of the apex, and mostly also by meristematic continuity of part of the ovary wall on the outside. By the latter the level of the openings of the nectaries on the ovary is defined. Septal nectaries in Monocotyledons are considered original.

On the morphology of the ovules in Salacca (Palmae)

Ano: 1988

URL: http://www.repository.naturalis.nl/record/525402

Female inflorescences in several stages of development of Salacca edulis Reinw. were collected from stands in the Kebun Raya at Bogor and near the village Depok, West Java. In addition to this, material of S. wallichiana Mart. collected in the Kebun Raya, Bogor, was used in this morphological study*). Salacca belongs to the subfamily Lepidocaryoideae of Palmae, which is distinguished by its large fruit scales. As one of the results of the present study I could observe that the early development of these scales takes place in the epidermal cells of the young ovaries. The Lepidocaryoideae are furthermore distinguished by the position of their ovules. In Palms there is one axillary basal ovule in each locule. Usually the ovules are ascendent and anatropous,...