The wall structure of the ‘reticulate’ cells of Conocephalum conicum (L.) Dum., observed by SEM

Abstract

SEM observations on the thallus of Conocephalum conicum after treatment with sodium hypochlorite show that the walls of the ‘reticulate’ cells constituting the hyaline parenchyma have thickenings (the ‘bars’) and large primary pit fields with a huge number of plasmodesmata-derived pores, on the unthickened areas of the walls. By contrast the parenchymatous cells constituting the nerve have plasmodesmata-derived pores, grouped in small sparse fields, especially on the transverse and oblique walls. It is suggested that the reticulate cells playa role in lateral distribution by symplastic and apoplastic conduction of solutes carried by the midrib.     

Torrubiella pruinosa,a teliomorph of an entomopathogenic fungus Hirsutella versicolor of mango hopper (Idioscopus clypealis) from India

Torrubeilla pruinosa, a teliomorph of an anamorphic entomopathogenic fungus Hirsutella versicolor on mango hopper (Idioscopus clypealis) was observed. On the infected mango hopper, tiny pin head signs of ascomata were observed. Ascomata of T. pruinosa is pale brown or tawny brown, crowded, immersed in stroma, wall dark golden brown, 260–320?×?230–260?μm, asci clavate, hyaline and thin walled. The ascospores of T. pruinosa are fusiform, distoseptate with a faint tint of pigmentation, 17.5–25.0?×?5.0–7.5?μm. The anamorph stage of H. versicolor fungal hyphae is hyaline, septate and profusely branched, and conidiogenous (phialides) cells are hyaline, pear-shaped and smooth-walled with single or double sterigmata and rarely, multiple sterigmata. Each sterigmata bears single conidia which are hyaline, oval to pear-shaped.     

Effect of thermocycling on hardness, absorption, solubility and colour change of soft liners

doi: 10.1111/j.1741‐2358.2010.00447.x
Effect of thermocycling on hardness, absorption, solubility and colour change of soft liners Objective: The effect of artificial ageing on the hardness, absorption, solubility, and colour of soft denture liners was investigated. Materials and methods: Liner materials based on acrylic resin (Trusoft) or silicone (Dentusil, Ufi Gel P, and Ufi Gel SC) were tested before and after 2000 thermal cycles. A total of 20 specimens of each material were tested. Half of the specimens were used for hardness and colour evaluation, and the remainder for absorption and solubility tests. The hardness evaluation was carried out using a Shore A durometer, while absorption and solubility tests were performed by storing samples in a desiccator and weighing daily until reaching constant mass (W1). After thermocycling, the samples were again weighed (W2) and dried (W3). Colour was measured using a spectrophotometer. Statistical analysis was performed using GraphPad InStat at the p < 0.05 level. Results: Thermocycling significantly affected the hardness of the specimens. The Trusoft material exhibited the highest absorption (1.48 ± 0.48), solubility (1.26 ± 0.28), and colour change (3.92 ± 0.33), significantly different from the other materials. There were no significant differences among the silicones in terms of absorption, solubility, and colour change, except for the colour of Dentusil, which changed (0.83 ± 0.11). Conclusion: It can be concluded that silicone liners performed significantly better compared to acrylic resin.     

Development of the hyaline layer around the planktonic embryos and larvae of the asteroid Patiriella calcar and the presence of associated bacteria

Summary

The hyaline layer (HL) around the embryos and larvae of Patiriella calcar is examined by transmission electron microscopy. P. calcar hatches at the gastrula stage and develops through a lecithotrophic planktonic brachiolaria. The hyaline layer of unhatched P. calcar is poorly developed and is comprised of wispy fibrils scattered among the epithelial microvilli. Fibrils are also occasionally seen associated with the inner surface of the fertilization envelope. By the hatched gastrula stage, the hyaline layer is organized into three strata: the intervillous layer, the supporting layer and the coarse outer meshwork layer. Seven-day-old brachiolaria also have a hyaline layer comprised of three strata. In these larvae the supporting layer elevates away from the epithelial surface due to the tuft-like organization of the underlying microvilli. This results in the formation of local outpockets giving the surface of the HL a lobed appearance. Bacteria are occassionally seen in the intervillous layer, particularly in association with the outpockets. These bacteria are phagocytosed by the epithelial cells and, in larvae that have bacteria, may play an augmentive role in larval nutrition. The structure of the hyaline layer of P. calcar is compared with that of the hyaline layer of other Patiriella species to determine if it is more similar to the external coats around its planktonic (P. regularis) or benthic (P. exigua) developing congeners. The comparison shows that the hyaline layer of P. calcar is virtually identical to that of P. regularis, a similarity that may reflect the pelagic life histories of these species.     

The composition and importance of the phytoneuston in two floodplain lakes in south-eastern Australia

Normans Lagoon and 3-Gum pond are small floodplain water bodies adjacent to the Murray River, south-eastern Australia, and often have a visible film/sheen across their surface. Since few studies have provided quantitative comparisons of the surface and subsurface layer communities of shallow freshwater lakes, we determined the contributions of the surface and subsurface populations to overall algal biomass when a surface film was visible, and when it was not visible. We examined the algae and cyanobacteria present at the air–water interface of each water body, and compared the findings with those for the water immediately below the surface, and for the overall water column. The algal groupings Trachelomonas spp., other Euglenophyceae (principally Euglena spp.), Chlorophyceae and Cyanobacteria usually comprised >95% of the measured biovolume within all samples. Samples from the air–water interface were considerably enriched (up to 200-fold) with respect to algal biovolume, whether or not a visible surface film was present, and elevated cell counts were observed within the air–water interface for motile organisms such as Trachelomonas spp. and green unicellular flagellates. The reverse was true for the cyanobacterium Planktolyngbya however, with greater concentrations occurring at depth. In terms of its contribution to the overall algal/cyanobacterial populations within each water body, the surface layer was found to be responsible for <1–20% of the biovolume over the entire water column. Multivariate statistical analysis confirmed there were significant differences between the communities of the air–water interface and those of the water below, and that these differences occurred both in the presence and absence of a visible surface film/sheen. Handling editor: D. Ryder     

<Emphasis Type="Italic">Cylindrosporella</Emphasis> on betulaceous trees in Japan

Three Cylindrosporella species on the leaves of betulaceous trees – C. carpini, C. coryli, and C. microsperma – were first reported from Japan. The genus Cylindrosporella is sometimes treated as congeneric with Asteroma; however, we considered these to differ based on conidial morphology following the concept of Arx. The genus Cylindrosporella is characterized by one-celled, filiform or fusiform, small conidia that are often curved, have hyaline, thin walls, and are produced from phialidic conidiogenous cells in subcuticular, fiat acervuli. The three species are distinguished from each other on the basis of conidium size. Received: September 27, 2001 / Accepted: November 5, 2001     

Feather colours of live birds and museum specimens look similar when viewed by seabirds

Bird plumage and skin colour can be assessed from museum specimens. To determine whether these accurately represent the colours of live birds when viewed by birds themselves, we analysed the spectral reflectances of live and up to 100‐year‐old museum specimens of five seabird species (White‐faced Petrel Pelagodroma marina, Common Diving Petrel Pelecanoides urinatrix, Grey‐faced Petrel Pterodroma gouldi, Little Shearwater Puffinus assimilis and Fluttering Shearwater Puffinus gavia). Live birds had brighter colours than museum specimens, but there were no significant differences in the wavelengths reflected. Modelling indicated that seabirds would be able to detect colour changes in the skin, but not the feathers, of museum specimens, but only for species with blue or pink feet (Pelecanoides urinatrix and Puffinus assimilis). For seabirds, museum specimens are adequate proxies for feather colour but not for skin colour.     

Taxonomic re-evaluation of the Azolla genus in Portugal

ABSTRACT

The Portuguese and the European Flora refer to the presence of two or three Azolla species in Portugal: A. filiculoides Lam., A. caroliniana Willd. and/or Azolla mexicana Presl., the latter included in the last edition of Flora Europaea. In the present work, the taxonomy of Azolla species is reviewed using the two most important characters that can distinguish between these two/three species: papillae in the dorsal leaf lobe and perine architecture of the megaspore apparatus. Other characteristics, such as the hyaline border cells of the dorsal leaf lobes and the number of glochidia septa in microsporangium massulae, are also used. All the Azolla specimens, collected from several locations in Portugal, were identified as Azolla filiculoides Lam. This identification disagrees with previous published reports on Azolla taxonomy in Portugal as well as with herbarium identification.     

Fine structure of wing scales of butterflies, Euploea mulciber and Troides aeacus

Wing scales of male Euploea mulciber (E. mulciber) and Troides aeacus (T. aeacus) butterflies were investigated from interest in photonic crystal by scanning electron microscopy and optical reflectance measurement. On the basis of the structural observation, the colouration in different areas in their wings was discussed. It was particularly deduced that a violet-green iridescence characteristic of E. mulciber’s forewing is caused only in a wavelength range from ∼380 to ∼510 nm by multiple interference from a highly tilted, triple-layered cuticle arrangement on the brown scales. It was also found that T. aeacus does not produce a blue-green sheen such as observed by Troides magellanus because its scales have no multiple cuticle layers but microrib layers unable to produce any backscattering diffraction.     

Description ofGerres chrysops sp. nov. From Thailand and redescription ofGerres setifer (Hamilton, 1822) andG. Decacanthus (Bleeker, 1865) (perciformes: Gerreidae)

Gerres chrysops, a new gerreid species from the Gulf of Thailand, is described on the basis of 29 specimens, 58–83 mm in standard length (SL). A small-sized species (less than 100 mm SL), it is characterized by a silvery-gold sheen on the head and trunk, vivid yellow or yellowish-hyaline fins in life, two supraneural bones (formula 0/0/2/) and dorsal fin rays usually IX, 10. The new species is similar toG. decacanthus (Bleeker, 1865) andG. setifer (Hamilton, 1822), which are redescribed. being similarly small valid gerreid species characterized by two supraneural bones. Together, the three species comprise “theGerres setifer complex.”Gerres chrysops differs from bothG. decacanthus andG. setifer in life and fresh colors, the body being silvery-gold with vivid yellow or yellowish dorsal, caudal, anal and pelvic fins, and yellowish-hyaline pectoral fins (vs. silver body with hyaline fins in the latter two species).Gerres setifer differs fromG. chrysops andG. decacanthus in having the last dorsal fin spine longer than the penultimate spine (vs. almost same length or shorter), usually ten dorsal fin spines and nine soft dorsal rays (vs. usually IX, 10), and 8 or 9 lower series gill rakers (vs. usually 7).Gerres decacanthus differs fromG. chrysops andG. setifer in having a shorter head, lesser body depth at the first anal fin spine base, lesser body width at the pectoral fin base, and shorter second dorsal and third anal fin spines. The new species is currently known only from Angsilla, near Bangsaen, and around Si Chang Island, northeastern Gulf of Thailand.Gerres decacanthus inhabits southern Chinese waters andG. setifer is currently known from the Bay of Bengal to the Andaman Sea.     

A new blue-grey Veturius (Publius) Kaup of the northwestern Sierra de Talamanca,Costa Rica (Coleoptera: Passalidae)

A new species of Veturius (Publius) Kaup, V. unanus n. sp., from a mountain cloud forest of Costa Rica, northwestern Sierra de Talamanca, Tapantí-Río Macho Massif, Province of Cartago, is described and illustrated. It is the first known Publius species with a blue-grey body color, matt elytra and shining or satiny elsewhere. The species is interpreted as sister species of V. (Publius) talamacaensis Boucher, 2006, from which it differs by a few characters. Both species are sympatric. V. unanus n. sp. is the northernmost endemic in the subgenus Publius.     

The “hyaline body” of the root parasiteAlectra orobanchoides benth. (Scrophulariaceae)—Its anatomy,ultrastructure and histochemistry

Summary Differentiation of a specialized tissue, the so-called hyaline body, has been demonstrated in the haustorial neck of the root parasite,Alectra orobanchoides, growing on some of its hosts,Helianthus annum L. andSesamum indicum L. This body is characterized by small, but densely structured cells and unusual extracellular deposits. The entire tissue, as well as the deposits, enlarge drastically during development of the parasite. The hyaline tissue is closely associated with conductive elements-especially the phloem-which traverse and surround the body. Histochemical characterization of the extracellular deposits revealed a polysaccharidic as well as proteinaceous components. The possible role of the hyaline body is at present still obscure.     

Macromitrium maolanense Zeyou Zhang,D.D.Li,Jing Yu & S.L.Guo,a new species from China based on molecular and morphological evidence

Introduction. During a field excursion in Guizhou Province, China, we collected some interesting moss specimens with branch leaves subulate in the upper part, partially and variably bistratose laminae, and a Macromitrium-like epiphytic growth habit on tree trunks. We present morphological and phylogenetic arguments for recognising these plants as a new moss species in the genus Macromitrium Brid. (Orthotrichaceae).

Methods. We compared the morphology of the potential new species with closely related species of Macromitrium, and constructed a phylogenetic tree based on ITS2, trnL and trnG including sampling from 14 other morphologically similar species of Macromitrium.

Key results. The proposed new species belongs to the genus Macromitrium (Orthotrichaceae, Musci). It is closely related to M. gymnostomum Sull. & Lesq. in the phylogenetic tree and according to gametophytic morphological features, represents a hitherto undescribed species.

Conclusions. A new moss species, Macromitrium maolanense Zeyou Zhang, D.D.Li, Jing Yu & S.L.Guo, is described and illustrated. The new species can be distinguished from all congeners by the combination of the following features of the branch leaves: (1) oblong-lanceolate, lanceolate to linear-lanceolate, gradually narrowed to an easily broken subula; (2) rather obscure upper and medial cells, often with blackish stains among cells, densely pluripapillose; (3) variably and partially bistratose laminae in the upper 1/3 portion; (4) basal cells clear, hyaline and smooth, those near costae forming a ‘cancellina region’; and (5) with numerous brownish, clavate gemmae on upper portion. We also discuss the principal distinctive characters separating the new species from its nearest congeners.     

New species of the subfamily Conoderinae (Coleoptera: Curculionidae) in Dominican amber

Eulechriops argyrosoman. sp. (Curculionidae: Conoderinae: Lechropini) and Geratozygops platysoman. sp., Geratozygops stenosoman. sp. and Geratozygops arsinotusn. sp. (Curculionidae: Conoderinae: Zygopini) are described from Dominican amber. The small size, nearly parallel sides of the pronotum and silvery sheen distinguish Eulechriops argyrosoma from extant members of the genus, which have not been recorded from Hispaniola. Size and rostral and pronotal characters separate the three Geratozygops species from the single species (Geratozygops atropos) previously described from Dominican amber.http://www.zoobank.org/urn:lsid:zoobank.org:pub:89BC7F43-6C1A-4A6A-839B-CE94C7F6F140     

Progress and Development in Biological Education

Software

Transpiration By J. M. Garland and U. Garland. Written for BBC Model B with colour monitor, cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth PL9 9AF. Price £10.00. Reviewd by W. G. Rogers

Seed germination By J. M. Garland. Written for BBC Model B with colour monitor. Cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth, Devon PL9 9AF. Price £10.00 Reviewd by W. G. Rogers.

Photosynthesis By J. M. Garland.Written for BBC Model B with colour monitor, cassette and disc versions. Produced by Garland Computing, 35 Dean Hill, Plymouth PL9 9AF. Price £10.00 Reviewed by W. G. Rogers.

Slides/Strides

Vertebrate reproduction Twenty-two.35 mm colour slides (including two title slides) with a study guide by David W. Macdonald. Ref. AV 218, price £16.80. Available from: Oxford Educational Resources Ltd, 197 Botley Road, Oxford 0X2 OHE Reviewed by Katrina Fuery

Reproduction in mammals Twenty-two.35 mm colour slides (with two title slides) with teaching notes by David W. Macdonald, produced in association with Oxford Scientific Films Ltd and J. Dellar of Wildlife Consultants Ltd. Ref. AV 220, price £16.80. Available from Oxford Educational Resources Ltd, 197 Botley Road, Oxford OX2 OHE Reviewed by Claire Carpenter

Mitosis and meiosis Two sets of 12 slides, each accompanied by a booklet containing background information and questions with answers. By Dr Judith Kinnear and Dr Marjory Martin. Refs M39825/8, M39820/9, price £9.95 each. Available from Philip Harris Biological Ltd, Oldmixon, Weston-super-Mare, Avon BS24 9BJ Cathy Maclean Marjorie Tindal

Farm animal breeds Set of 24, colour, plastic-mounted slides supplied in a wallet with teaching notes by Dr Alan Beaumont. Available from Audio-Visual Productions Ltd, Hocker Hill House, Chepstow, Gwent NP6 5ER Ref. 977. Price £8.90 Adam Cade

Basic techniques of plant tissue culture Twenty-six 35 mm colour slides in a plastic wallet with teaching notes. Ref M25080/2, price £16.25. Also available as a filmstrip, ref. M25084/9, price £11.00. Obtainable from Philip Harris Biological Ltd, Oldmixon, Westonsuper-Mare, Avon BS24 9BJ V. E. Stein

Focus on bats Forty 35 mm plastic mounted colour slides and a 20 minute cassette soundtrack narrated by Dr R. Stebbings. Ref. A VP 080. Price £11 (or filmstrip £7) and tape £4 (inclusive of VAT and postage). Available from International Centre for Conservation Education, Greenfield House, Gutting Power, Cheltenham, Glos GL54 5TZ Kevin Walsh

Introducing British reptiles Forty 35 mm colour slides, commentary booklet, and a leaflet on ‘Being kind to snakes‘ are supplied in a handy plastic wallet. Ref. AVP 075. Price £10.06 (includes VAT and postage). The commentary is also available on cassette. Also available as a film strip, price £5.00. Available from International Centre for Conservation Education, Greenfield House, Guiting Power, Cheltenham, Glos GL54 5TZ Iain Armstrong

Introducing British amphibia Forty 35 mm colour slides, commentary booklet and a leaftlet on ‘Garden ponds as amphibian sanctuaries’. Ref AVP 074. Price £10.06 (includes VA T and postage). Also available as a film strip, price £5.00. An audio-cassette of the commentary will soon be available price £3.80. From International Centre for Conservation Education, Greenfield House, Guiting Power, Cheltenham, Glos GL54 5TZ Alison Muspratt

Videotapes

Investigating the nervous system A 20-minute video-cassette, ref. 84/031/ I, price £29.50. Also available as a 16 mm film price £395. Produced by Educational Media Australia, in association with the Australian Academy of Science, Schools Biology Project. Available from Educational Media International, 25 Boileau Road, London W5 3AL Jane O'Leary

Reproduction in organisms A 16-minute video-cassette released in 1981, ref. 84J062JR, price £29.50. Also available as a 16 mm film price £205, ref. EM A AUS UP-S. Produced by Educational Media Australia. Available from Educational Media International, 25 Boileau Road, London W5 3AL Carol Burton Jenny Johnson

Eat your heart out A videotape in two parts, lasting about an hour produced by Scope Films Ltd, and available from Concorde Films Council Ltd, 201 Felixstowe Road, Ipswich IP3 9BJ. Price: hire £10; sale £60 C. Thorpe P. Burdett

Tapes

Biorhythms: 1. Human biology; 2. General biology Each consists of a cassette tape and a 65+ page booklet. Words by Harold Baum, music by Peter Shade, sung by the ‘Metabolites’. Published by Learn Through Music Ltd. Distributed by: (UK) Taylor and Francis Ltd, 4 John Street, London WC1N 2ET; (USA) Taylor and Francis Inc., 242 Cherry Street, Philadelphia, PA 19106-1906. Each part £8.95 (1984). ISBNs 0 85066 291 5 and 0 85066 292 3 John A. Barker     

Die Redoxpigmente von Carausius morosus und ihre Bedeutung für den morphologischen Farbwechsel

Summary From the epidermis of Carausius morosus two ommochromes were isolated, and identified by various means as Xanthommatine and Ommine. Their amount was determined by photometry for animals of different colour.Morphological colour change results mainly from changes in ommochrome content.If the lower part of their compound eyes is blackened, green specimens become brown by an increase of ommochrome production.This colour change can be evoked within a single larval instar.It can also be evoked in adult specimens, although to a small degree only.Dark specimens with unblinded eyes become paler under normal illumination in consequence of an increase of bright pigments and of the increase in bodysize, while the amount of ommochrome increases only very slightly.A decrease of ommochrome content or a loss of ommochrome by faeces or offshed cuticles was never observed.At high temperature (28° C) both, ommochrome production in the epidermis and melanin formation in the cuticle are increased.Implantation of supernumerous Corpora allata causes the ommochrome content to increase. After extirpation of the Corpora allata no decrease of ommochrome content is found but the green pigment, insectoverdin vanishes. Apparently in Carausius ommochrome may deposited but is never removed from the integument, which may explain the similar coloration after both experiments.     

Filamentous microbes indigenous to the murine small bowel: A scanning electron microscopic study of their morphology and attachment to the epithelium

Segmented, filamentous prokaryotic microorganisms colonize and attach to the cells in the epithelium of the mucosa of the small bowels of mice and rats. Scanning electron micrographs, derived from specimens of mouse small intestine, reveal microbial filaments of at least two types. One type is thin (0.8m) with only faint lines suggesting septa; the other is thicker (1.4m) and has distinct segments with pronounced septa. Most of the segments are rounded; a few are thin and elongated. Immediately surrounding the attachment site of these organisms, the surface of the epithelial cells appears roughened and occasionally stringy. The filaments may differ morphologically because they represent different phases in the life cycle of a single microbial type. Alternatively, however, they may differ because they are the cells of different microbial types colonizing the same epithelial habitat.     

Anthocyanic vacuolar inclusions--their nature and significance in flower colouration

The petals of a number of flowers are shown to contain similar intensely coloured intravacuolar bodies referred to herein as anthocyanic vacuolar inclusions (AVIs). The AVIs in a blue-grey carnation and in purple lisianthus have been studied in detail. AVIs occur predominantly in the adaxial epidermal cells and their presence is shown to have a major influence on flower colour by enhancing both intensity and blueness. The latter effect is especially dramatic in the carnation where the normally pink pelargonidin pigments produce a blue-grey colouration. In lisianthus, the presence of large AVIs produces marked colour intensification in the inner zone of the petal by concentrating anthocyanins above levels that would be possible in vacuolar solution. Electron microscopy studies on lisianthus epidermal tissue failed to detect a membrane boundary in AVI bodies. AVIs isolated from lisianthus cells are shown to have a protein matrix. Bound to this matrix are four cyanidin and delphinidin acylated 3,5-diglycosides (three, new to lisianthus), which are relatively minor anthocyanins in whole petal extracts where acylated delphinidin triglycosides predominate. Flavonol glycosides were not bound. A high level of anthocyanin structural specificity in this association is thus implied. The specificity and effectiveness of this anthocyanin "trapping" is confirmed by the presence in the surrounding vacuolar solution of only delphinidin triglycosides, accompanied by the full range of flavonol glycosides. "Trapped" anthocyanins are shown to differ from solution anthocyanins only in that they lack a terminal rhamnose on the 3-linked galactose. The results of this study define for the first time the substantial effect AVIs have on flower colour, and provide insights into their nature and their specificity as vacuolar anthocyanin traps.     

Two new species of the liverwort genus Riccia L. from tropical Africa: R. somaliensis and R. erubescens

Abstract

Two new Riccia species, R. somaliensis and R. erubescens from Africa are described and illustrated. They are both classified in the subgenus Riccia, section Riccia. R. somaliensis has hyaline, somewhat frilly scales and apolar, wingless spores; R. erubescens has shiny dark, purple-red to bright cherry-red scales and polar, winged spores with numerous small areolae; its tissues are sometimes distorted by gelatinous globules that are gradually extruded on the dorsal surface.