Showing papers in "Blumea in 1981"

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

Abstract: 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.

Structure and ontogeny of Stomata in Polypodiaceae

Abstract: The stomata as occurring on the fronds of the sporophytes of a large number of Polypodiaceae s.s. (Filicales) are investigated. A number of different stomatal types is recognised, (newly) described, and their ontogeny investigated. The different types of stomata are discussed in relation to their possible significance for tracing phylogenetic relationships in the Polypodiaceae following a cladistic analysis.

Wood anatomy, classification and phylogeny of the Melastomataceae

Abstract: A classification of the Melastomataceae, modified on the basis of wood anatomical evidence, is discussed. Three subfamilies (Crypteronioideae, Memecyloideae and Melastomatoideae) are recognized . Astronioideae, recognized in other classifications, are abolished and their constituent genera are classified in Memecyloideae (Pternandra) and Melastomatoideae (four genera of the tribe Astronieae). Wood anatomically Melastomataceae show affinities with a number of Myrtalean families, notably with Lythraceae, Onagraceae and Myrtaceae. The wood anatomy of ancestral ‘Protomelastomataceae’ is hypothesized and a tentative phylogeny is suggested for the extant subfamilies and tribes.

Inflorescence morphology of Loranthaceae – an evolutionary synthesis

Abstract: A systematized survey of inflorescence structure is presented of Loranthaceae, s.s., on a world-wide basis, starting with New World taxa and continuing with Old World ones. In each case, material is arranged to reflect a presumed evolutionary sequence. This sequence uses as its starting point the solitary sessile flower subtended by a foliage leaf, leading to the evolution of a determinate inflorescence with ebracteolate lateral monads, and eventually to indeterminate inflorescence types successively bearing ebracteolate and bracteolate lateral monads and, in many groups, eventually triads. Various trends in condensation to umbels and capitula have emerged occasionally, as well as other reductional phenomena and other modifications. The unit inflorescence of Loranthaceae is thus regarded as a fundamentally axillary structure, and not a modified leafy branch.

Wood anatomy of the Neotropical Melastomataceae

Abstract: The wood anatomy of 47 genera of the neotropical Melastomataceae is described in detail. The wood anatomy of the neotropical part of this pantropical family supports the subdivision into two groups: the subfamily Memecyloideae (the genus Mouriri) and the subfamily Melastomatoideae (all other genera). A relationship of Mouriri with other representatives of the family is not supported by the wood anatomical characters, because of differences in fibre type, vessel distribution, and the fibre length/vessel member length ratio, and the presence of included phloem in Mouriri. The subfamily Melastomatoideae is a fairly homogeneous group. Although some characters are very pronounced in some tribes and scarce or absent in other tribes, most tribes show a wide overlap in their wood anatomical features. An important means to distinguish to a certain extent between tribes is the size and shape of the intervascular pits combined with the size and shape of the vessel—ray and vessel—parenchyma pits. Three groups can be recognized: type 1. all pits round to slightly oval; type 2. intervascular pits round to oval, and the vessel—ray and vessel—parenchyma pits more elongated, oblong to scalariform; type 3. all pits round to oblong and scalariform. Other diagnostic characters are the parenchyma distribution, and the distribution of the fibre pits. The tribe Blakeeae can be separated from the other tribes due to the presence of druses and 2-4-seriate rays. The relationship between wood anatomical characters and habit and habitat, as well as possible phylogenetic trends in the family and classification of the neotropical tribes are discussed.

Wood anatomy of the Palaeotropical Melastomataceae

Abstract: The wood anatomy of the palaeotropical Melastomataceae is described in detail on the basis of 134 samples of 107 species from 36 genera. On the wood anatomy, three subfamilies are recognized, Memecyloideae, Melastomatoideae, and Crypteronioideae. The Memecyloideae stand out through their fibre-tracheids, the deviating fibre length/vessel member length ratio, and the scanty paratracheal to aliform parenchyma. The Melastomatoideae are characterised by libriform fibres showing fibre dimorphism and rays composed of erect, square, and weakly procumbent cells (also in Memecyloideae p.p.). The subfamily Astronioideae is abolished; Pternandra is transferred to Memecyloideae, the Astronieae fit perfectly in the Melastomatoideae. Within Melastomatoideae the tribes are not easy to separate. The subtribe Dissochaetineae (all climbers) of the Dissochaeteae stands out because of its multiseriate rays, subtribe Medinillineae has scalariform inter-vessel pits; Astronieae have longest vessel members of the palaeotropical Melastomataceae, uniseriate rays, and bands of deviating fibres in which axial parenchyma is scarcely present: in the Osbeckieae apotracheal parenchyma bands (probably originated through fibre dimorphism) characterise the wood of Dichaetanthera; it is proposed to combine Oxysporeae and Sonerileae to one tribe Sonerileae; on the basis of the inter-vessel pitting two subtribes are recognized, different in delimitation from the two original tribes. The family Crypteroniaceae s.s. (Axinandra, Crypteronia and Dactylocladus) is incorporated in Melastomataceae as a separate subfamily. The scalariform inter-vessel pits, present in palaeotropical Melastomataceae only, must be interpreted as a specialization from the alternate pattern. Raphides are present in one species of Bredia, B. tuberculata. Clustered crystals are observed in the axial parenchyma and rays of Dichaetanthera. Large elongate crystals are present in the parenchyma of the strands of axially included phloem of the Memecyloideae. Variation in quantitative characters (vessel member length, vessel diameter and frequency) can partly be explained from the ecological preference of the species concerned. Wood anatomical differences between lianas and erect relatives are discussed.

Four frequently confused species of Typhonium Schott (Araceae)

Abstract: Typhonium trilobatum, T. flagelliforme, T. roxburghii, and T. blumei are taxonomically distinct, but their epithets (including that of T. divaricatum, nom. illegit.) frequently have been interchanged, primarily because of nomenclatural problems involving synonymy and (mis)typifications. It is concluded that the last monographer (Engler, 1920) used the correct names for the four species, except for what he called T. divaricatum, here called T. blumei.

A note on stomatal types and crystals in the leaves of Melastomataceae

Abstract: Original data on leaf crystals and stomatal types in 25 genera of Melastomataceae are presented, and discussed with reference to the classification of the family as modified by Van Vliet et al. (1981, this issue). The heterogeneity of the abolished subfamily Astronioideae is confirmed and a separation of Pternandra from the Astronieae is also justified on the basis of leaf anatomical data. The Astronieae are characterized by large styloids and predominantly anomocytic stomata; this combination of characters also occurs in part of the Melastomatoideae (especially the Miconieae). Most other Melastomatoideae are characterized by polocytic to diacytic stomata and druses. The subfamilies Memecyloideae and Crypteronioideae remain rather heterogeneous leaf anatomically, but the evidence can be interpreted in support of mutual affinities.

Florae Malesianae Praecursores LXII. On the genus Thottea (Aristolochiaceae)

Abstract: The generic delimitation of Thottea and Apama has been reviewed. Arguments are given for treating them as one genus, under the name of Thottea. Techniques used for clearing the leaves and for preparing reproductions of the venation have been described. There are two leaf venation patterns, i.e. pinnate and acrodromous, with intermediate forms showing gradual variation. The arrangement of stamens, chief character used for generic distinction, up until now known as occurring in one series (Apama) or two (Thottea), has now also been found existing in three or four series. One new type of seeds in this group has been found, which is rather smooth, flat and longitudinally curved. It resembles that of Saruma and some species of Aristolochia. Scanning electronmicrographs of leaf surfaces, floral parts and seeds have been chosen to elucidate interesting or diagnostic characters. There are eight new species described and eight new combinations made.

A taxonomic revision of the genus Arthraxon Beauv. (Gramineae)

Abstract: A world-revision of Arthraxon Beauv. ( Gramineae) is presented. Three wide-spread species, A. hispidus (Thunb.) Makino, A. lanceolatus (Roxb.) Hochst., and A. lancifolius (Trin.) Hochst. are very variable and have caused the description of a great number of taxa, most of which are here reduced to synonomy. There are now 7 species and 9 varieties; for 6 of the latter new combinations are proposed. No new taxa are described.

Comparative leaf anatomy of the Asiatic Myristicaceae

Abstract: The leaf anatomy of c. 60 species of the four Asiatic genera of the Myristicaceae (Gymnacranthera, Horsfieldia, Knema and Myristica) is described in detail. Myristicaceae have characteristic, uniseriate hairs, the cells of which have arms. The number of arms per cell and the relative length of the arms are important characters to separate the Asiatic genera. The hairs of Knema can be classified further into different types. Many species of Myristicaceae have a layer of cutinaceous, alveolar material overlying the cuticle proper on the abaxial leaf surface. In angiosperms such a layer was hitherto only reported for Winteraceae. Guard cells are often embedded in the subsidiary cells. The paracytic stomatal complex in Knema and Myristica is sunken and overarched by typically arranged bordering cells, leaving a starshaped opening in Knema and forming a ring in Myristica. The vascular system of the midrib is composed of an abaxial and adaxial collateral bundle (the latter is absent from Gymnacranthera). and there are always free phloem bundles in the centre. The diagnostic and taxonomic value of these and many other varying leaf anatomical characters is analysed and discussed. Much of the leaf anatomical variation can be used for species grouping and identification, and the four genera can easily be separated on leaf anatomical characters (see table V, and synoptical keys at the end of this paper). Leaf anatomy lends little support to a close affinity of Myristicaceae with Annonaceae and Canellaceae, and although the family shows several typically Magnolialean characters (e.g. oil cells, paracytic stomata) leaf anatomy points to a fairly isolated position of the family within the order Magnoliales. Many of the leaf anatomical characters of Myristicaceae are highly xeromorphic. This is discussed in relation to the markedly mesic ecology of the family.

The genus Rubus (Rosaceae) in Malesia. 1. Subgenera Chamaebatus and Idaeobatus

Abstract: In subgenus Chamaebatus two Malesian species are recognized, in subgenus Idaeobatus 18. Synonymy, descriptions, and habitat notes are given, sometimes extending to, but not complete for, extra-Malesian parts of the species areas. No new names or combinations are published. Keys are given to the species.

Transmission electron microscopy of apical cells of Sphacelaria spp. (Sphacelariales, Phaeophyceae)

Abstract: The ultrastructure of apical cells of six species of Sphacelaria (S. arctica, S. cirrosa, S. nana, S. racemosa, S. radicans, and S. rigidula) is studied here. In most details such as ultrastructure of chloroplasts, mitochondria, microbodies, nuclei and centrioles all Sphacelaria species studied are similar. Only in sections of S. rigidula, however, do pyrenoid-like structures occur.

Comparative morphology of the gametophyte of some Thelypteroid ferns

Abstract: A study of the development of the gametophytes of sixteen thelypteroid ferns reveals similarities and significant differences among them. Combinations of the diversified features of the prothalli appear to have a tremendous impact on identification and delimitation of the major taxa, and support the views of those authors who propose the taxonomic segregation of these ferns.

Two new orchids from Orissa

Abstract: Haines (1924), Fischer (1928), Mooney (1950), Panigrahi et al (1964), and other workers’ from their studies on the vegetation and flora of Orissa recorded 25 genera and 54 species belonging to the family Orchidaceae. Exhaustive collections made by me since 1968 have yielded a wealth of varieties of forms of orchids, which I have identified with 100 taxa (excluding certain novelties) belonging to 31 genera. I describe here one new species and a variety of the genus Habenaria Willd. Both the taxa resemble in general Habenaria foliosa A. Rich., but differ from it by a number of diagnostic characters.

Supplementary data on Malesian Knema (Myristicaceae) including three new taxa

Abstract: Among the collections of Knema acquired by the Rijksherbarium since the publication of my new account of the genus Knema, in Blumea 25, 1979: 321 — 478, a few specimens caused problems with the identification, and at closer examination these yielded facts of interest which are published here. Some specimens represented stages not yet known, for instance fruits, or male flowers, while other specimens meant a significant range extension of the species. Two new species and one new subspecies are described. For easy reference, the sequence and numbers of the species presently treated correspond with the numbers as used in the account of 1979. The new species bear the number of the species after which they appear in the general key of 1979, with the addition ‘-bis’.

A note on New Caledonian Epacridaceae

Abstract: Thirty pre-1975 and 22 post-1974 collections of Epacridaceae from New Caledonia are added to the exsiccatae in Virot’s 1975 revision of New Caledonian Epacridaceae. A collection of Styphelia cordifolia purported to be New Caledonian is shown to be of Australian origin.