Comparative floral structure and systematics of Pelagodoxa and Sommieria (Arecaceae)

Floral structure is compared in Pelagodoxa and Sommieria (Arecaceae, Arecoideae). Male flowers have three free, imbricate sepals, three basally congenitally united and apically valvate petals, and six stamens. Anthers are dorsifixed and dehiscence introrse. The sterile gynoecium is tricarpellate. Female flowers have three free, imbricate sepals and three free, imbricate petals, which are slightly fused with the sepals at the base. Four to six staminodes are congenitally united at the base and fused with the ovary for a short distance. The gynoecium is syncarpous. Carpels are almost equal in early development; later the gynoecium becomes pseudomonomerous. The three stigmatic branches are equally developed, apical and sessile. The carpels are (syn-)ascidiate up to the level of the placenta and (sym-)plicate above. Each carpel has one ovule, in the sterile carpels it is aborted at anthesis. The fertile ovule is erect up to anthesis and pendant afterwards because of the bulging out of the ovary. Pollen tube transmitting tracts (PTTT) encompass the secretory epidermis of the ventral slits of each carpel. Floral structure in Pelagodoxa and Sommieria supports the sister group relationship between the two genera suggested in recent molecular phylogenies and reflects their close relationships to a major clade of pseudomonomerous arecoid palms from the Indo-Pacific region.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 27–39.     

Analysis of a Surface Antigen of Pneumocystis carinii

The 115 kd band in polyacrylamide gels is a major antigen of Pneumocystis carinii . Data obtained from treatment with enyzmes, binding to lectins, and labelling the surface with biotin suggest that this moiety is a glycoprotein containing mannosyl/glucosyl and N-acetylglucosamine residues, and that it is located on the cell wall of the organism. Other rat and human P. carinii antigens also are glycoproteins but differ in specific protein or carbohydrate residues or location on the organism.     

A synopsis of the genus Atypus (Araneae, Atypidae)

Twelve of sixteen Atypus species previously described, and one undescribed, are examined. Atypus javanus Thorell is re-diagnosed and the male is described. The vulva of this species, and of A. coreanus Kim and A. karschi Dönitz, arc illustrated for the first time. The taxonomic characters given by Kraus & Baur [ Verh, naturw. Ver. Hamb. 17 : 85–116(1974)] and additional details of male-and female genital organs are discussed. A granular texture on male chelicerae and front legs, presumably a stridulatory apparatus, is noted and used for distinguishing species. A deep cymbial pit of unknown function is illustrated and discussed. Specific character combinations for the species examined are presented in a table. Notes on relationships, habitat, zoogeography, web, phenology and development are given.     

Ultrastructural Observations on the Infection of Rat Liver by Plasmodium berghei Sporozoites In Vivo1

The invasion of liver parenchymal cells by sporozoites of Plasmodium berghei Vincke & Lips, 1948, was studied in vivo using transmission electron microscopy. Livers of Brown Norway rats were examined 30 and 60 min after intraportal injection of 15 million sporozoites each. Sporozoites found after incorporation into vacuoles in hepatocytes were often located near a bile canaliculus at the lateral cell surface, surrounded by hepatocyte lysosomal structures; however, degradation of sporozoites caused by lysosomal digestion inside hepatocytes was never observed. Due to the crescent shape of sporozoites, serial sections were necessary to demonstrate the actual process of invasion of the hepatocyte. The hepatocyte's plasmalemma appeared to invaginate due to the sporozoite's action, thereby creating a parasitophorous vacuole. It was suggested that the sporozoite actively penetrated the hepatocyte; however, no visible depletion of rhoptries and micronemes was observed.     

Trypanosoma rhodesiense Bloodstream Trypomastigote and Culture Procyclic Cell Surface Carbohydrates1, 2, 3

Bloodstream trypomastigote and culture procyclic (insect midgut) forms of a cloned T. rhodesiense variant (WRATat 1) were tested for agglutination with the lectins concanavalin A (Con A), phytohemagglutinin P (PP), soybean agglutinin (SBA), fucose binding protein (FBP), wheat germ agglutinin (WGA), and castor bean lectin (RCA). Fluorescence-microscopic localization of lectin binding to both formalin-fixed trypomastigotes and red cells was determined with fluorescein isothiocyanate (FITC)-conjugated Con A, SBA, FBP, WGA, RCA, PNA (peanut agglutinin), DBA (Dolichos bifloris), and UEA (Ulex europaeus) lectins. Electron microscopic localization of lectin binding sites on bloodstream trypomastigotes was accomplished by the Con A-horseradish peroxidase-diaminobenzidine (HRP-DAB) technique, and by a Con A-biotin/avidin-ferritin method. Trypomastigotes, isolated by centrifugation or filtration through DEAE-cellulose or thawed after cryopreservation, were agglutinated by the lectins Con A and PP with agglutination strength scored as Con A < PP. No agglutination was observed in control preparations or with the lectins WGA, FBA or SBA. Red cells were agglutinated by all the lectins tested. Formalin-fixed bloodstream trypomastigotes bound FITC-Con A and FITC-RCA but not FITC-WGA, -SBA, -PNA, -UEA or -DBA lectins. All FITC-labeled lectins bound to red cells. Con A receptors, visualized by Con A-HRP-DAB and Con A-biotin/avidin-ferritin techniques, were distributed uniformly on T. rhodesiense bloodstream forms. No lectin receptors were visualized on control preparations. Culture procyclics lacked a cell surface coat and were agglutinated by Con A and WGA but not RCA, SBA, PP and FBP. Procyclics were not agglutinated by lectins in the presence of competing sugar at 0.25 M. The expression of lectin binding cell surface saccharides of T. rhodesiense WRATat 1 is related to the parasite stage. Sugars resembling α-D-mannose are on the surface of bloodstream trypomastigotes and culture procyclics; n-acetyl-D-galactosamine and D-galactose residues are on bloodstream forms; and n-acetyl-D-glucosamine-like sugars are on procyclic stages.     

Evolution of Neurohypophyseal Hormone Actions in Vertebrates

Arginine vasotocin (AVT) is one neurohypophyseal principle thathas been found in all vertebrates including the cyclostomes.Although many effects have been seen with administered AVT inmany vertebrate species, the physiological role of endogenousAVT is largely unknown. In this review, the evolution of therenal and vascular actions of AVT are discussed. Injection ofAVT produces diuresis in teleosts and lungfishes, but antidiuresisin tetrapods. In fishes and all tetrapods except birds, AVTis hypertensive. We have proposed that the renal responses canin fact be explained by the vascular responses. In our hypothesis,there are four types of responses to AVT. In type I, the peripheralvasculature is more responsive to AVT than the renal preglomerulararteriole so that AVT will cause a significant rise in systemicblood pressure and a net increase in the glomerular perfusion.This will then result in diuretic and pressor responses. Teleostsand lungfishes belong to this type. Type 11 is exemplified bythe mudpuppy which responds to AVT with antidiuresis and bloodpressure increase. This can be explained by an increase in sensitivityto AVT by the preglomerular arteriole so that AVT will causea decrease in glomerular perfusion even when systemic bloodpressure is increased. In type III which can be seen in thebullfrog, the vascular response to AVT will produce glomerularantidiuresis and blood pressure increase. In addition, tubularreceptors for AVT are also present and these receptors are involvedin the tubular reabsorption of water, thus enhancing the antidiureticresponse. Type IV as seen in mammals is mainly a tubular antidiureticresponse to ADH. Evidence in support of this hypothesis is givenin the paper. The above discussion concerns the renal and vascularactions of exogenous AVT. Our studies so far indicate that endogenousAVT is not the major regulatory mechanism in renal and vascularfunctions of the lungfish or bullfrog, although it may havea modulatory role.     

The feral goats of Kielderhead Moor

Herds of feral goats are present along the high ground of the Scottish Borders at the College, Hindhope, Kielderhead Moor (the study area), Bewcastle Fell and Roan Fell.
In the study area the nannies remained solitary, or in the company of their yearlings on the steep ground below the high moor throughout the winter. After the birth of their kids in March two female herds were formed each with a herd billy which came from the two male herds which were present through the winter on the high moor. The male herds left the study area in the spring and their ranges are not known. The two female herds maintained separate ranges on the high moor until the end of August when they combined into one large herd and were joined by a strange herd of billies which had not previously been seen.
After the first three or four days of its life the kid is left in a hiding place for most of the day whilst its mother ranges widely grazing with the herd. The kids join the herd when they are about six weeks old.
The Kielderhead Moor goats had a recruitment rate of 0–29/nanny/year and the females have a further expectation of life of 3–7 years. Figures for the billies are unreliable as disappearances of males from the moor are more likely to be the result of emigration than of deaths. While the herds of nannies have fairly restricted home ranges there is some evidence to suggest that many of the billies wander freely along the Borders.
In the early part of the summer the sheep and goats are eating very similar proportions of the plants present on the moor. Later on in the season there is a divergence with the sheep eating less Calluna while the goats eat less Eriophorum , but as the Trichophorum becomes available both animals include this in their diet.     

Recovery of Geotropism after Removal of the Root Cap

Removal of the cap from the primary roots of Zea mays and Triticumaestivum renders the roots unresponsive to gravity. In bothspecies a geotropic response is recovered before a new cap hasstarted to regenerate. Immediately after decapping amyloplastsstart to develop in cells of the root apex and it is proposedthat as the development of amyloplasts continues so they becomefunctional as gravity sensors. It is also suggested that theamyloplasts may be the source of an inhibitor that has beenpostulated to be the intermediary between the perception ofgravity and the geotropic response.     

Fine Structure of Trypanosoma cyclops in Noncellular Cultures*

The fine structure of the epimastigotes of Trypanosoma cyclops maintained in blood agar medium at 25 C is described. This organism was isolated from the Malaysian primates Macaca nemestrina and Macaca ira. A distinctive feature of T. cyclops is that it is pigmented when grown in the presence of hemoglobin. The pigment bodies apparently lack a substructure and are electron dense even in unstained sections. Most of the pigment is located posterior to the kinetoplast region but some is found adjacent and anterior to the kinetoplast. Cells from control cultures grown in medium lacking hemoglobin did not possess this type of pigment body. Similarly, pigment was not found in cells of an Indonesian trypanosome grown in medium containing hemoglobin. The cytoplasm of T. cyclops is bounded by a unit membrane which is specialized where it makes contact with the flagellum. A cytostome extends from the region of the flagellar pocket. The kinetoplast and nucleus are immediately posterior to the base of the flagellum. Transverse sections in the region of the flagellar pocket and flagellar base often reveal a group of 3 microtubules which are distinct from the pellicular microtubules.     

A generic revision of the Dorvilleidae (Polychaeta), with six new species from the deep North Pacific

PETER A. JUMARS
The Dorvilleidae are divided into eight genera: Dorvillea, Schistomeringos (new name), Protodorvillea, Meiodorvillea (new genus), Exallopus (new genus), Ophryotrocha, Parophryotrocha , and Apophryotrocha (new genus). Periodic maxillary replacement is found to occur in a manner which makes many often cited maxillary characters taxonomically unreliable. Therefore, the pharyngeal characters of all the type-species are redescribed or newly described. The discovery of new forms and the present interpretation of hard jaw parts permit construction of a phylogenetic scheme with Dorvillea as the most primitive genus containing living species. Suggestions are given for the advantageous use of the phenomenon of maxillary replacement in autecoiogical investigation.
Evidence is presented against the cosmopolitan distribution of Schistomeringos rudolphi , a species often noted in nearshore pollution studies. Newly described species are Dorvillea batia, Schistomeringos mediofurca, Meiodorvillea apalpata, Exallopus cropion, Ophryotrocha profunda , and Apophryotrocha mutabiliseta , all from the deep North Pacific. A key to the genera is provided, as are listings of all the known species within each genus.