First Half Of June Research Articles

Spirogyra species and accompanying algae from pools and ditches in The Netherlands

In ditches and moorland pools zygnematacean algae, especially Spirogyra, make up an important and often dominant component of floating algae. Of the total number of 60 Spirogyra species as yet recorded in The Netherlands, 47 species were recorded in ditches and pools. Sirogonium was represented by only one species, S. sticticum (Engl. Bot.) Wille, and Mougeotia and Zygnema by seven and six species, respectively. In hardwater ditches, especially at sites with relatively low pollution, Spirogyra forms a richly diversified component with up to ∼ 20 species per site. At hardwater sites with appreciable pollution, Spirogyra is suppressed or replaced by massive growths of algae such as Cladophora, Vaucheria, Enteromorpha or Hydrodictyon. At low alkaline and slightly acid sites, the number of species per site is considerably lower. Under conditions with pH values < 5, Spirogyra does not occur and is replaced by Mougeotia, Zygnema, Klebsormidium, Microspora and some others. The periodicity of Spirogyra species was studied. A peak in spore production occurs in the second half of May and the first half of June. Spores were more frequently observed in hardwater habitats than in low-alkaline environments. Most species have wide ranges of occurrence; 22 species were found in low alkaline and slightly acid habitats, but most of these species are not restricted to such environments. Presumably they are adapted to nutrient-poor conditions. In eutrophic hardwater ditches, Spirogyra granulata Jao and S. singularis Nordst. appeared to be very tolerant to pollution. Species such as Spirogyra nitida (Dillw.) Link and S. majuscula Kütz. seem to indicate seepage of groundwater in otherwise nutrient-rich environments.

The ecology of germination and reproduction of less frequent and vanishing species of the Czechoslovak flora I.Alyssum saxatile L.

Lhotska M. (1988): The ecology of germination and reproduction of less frequent and vanishing species of the Czechoslovak flora I.Alyssum saxatile L.—Folia Geobot. Phytotax., Praha, 23: 321–324.—The conditions of germination of both fresh and stratified seeds ofAlyssum saxatile were investigated in the laboratory at 13 various temperature values. The temperature of 15/25°C was found to be optimum. In stratified seeds germination was accelerated, and the range of range of temperatures suitable for germination became wider. Seeds sown out after ripening sprouted in the first half of June, and by autumn they developed rather robust rosettes.

Naissance de l'«Assemblée Nationale»

On the day after their royal opening on 5th May 1789, the Estates General began their sittings in three separate houses. That of the Third Estate took the name of «Commons », but in its first sitting on 6th May, the deputy Malouet spoke of the «National Assembly ». This expression was used during the month of May and the first half of June by several speakers in the «Commons » and was even used in the Nobles'House. A few representatives of the clergy joined the Third Estate between the 13th and 16thJune and, at Sièyes's suggestion, the Commons decided on 17th to form the National Assembly. This decision has been considered as the first revolutionary act of the Third Estate and the clerical minority.

SPIROGYRA SPECIES AND ACCOMPANYING ALGAE FROM DUNE WATERS IN THE NETHERLANDS

SUMMARY A survey is given of the occurrence of filamentous algae from dune pools situated in the calcium carbonate-rich dune area at Oostvoorne and Egmond-Castricum as well as the calcium carbonatepoor Wadden area at Terschelling. Spirogyra and Oedogonium were important and often dominant components at these sites and were represented by at least 35 and 20 species respectively. Accompanying species belonged to Zygnema, Mougeotia, Bulbochaete, Microspora and Tribonema. In several pools Chara was dominant. Mass occurrence of filamentous algae was frequently observed. The seasonal dynamics of the components in floating mats were described. Periodicity phenomena of components and individual Spirogyra and Oedogonium species were studied. A peak in spore production of Spirogyra was situated in the second half of May and the first half of June. Based on physico-chemical data, the water of most of the investigated pools can be characterized as mesotrophic freshwater with a moderate or high amount of calcium and bicarbonate. Water quality differences between Terschelling (low alkalinity) and Egmond-Castricum/Oostvoorne (high alkalinity) were reflected in their species composition. Most of the species from the dune pools are also known from other more nutrient-rich habitats in The Netherlands, but there are differences in quantities and combinations of species.

Megagametogenesis, fertilization, and embryo development in Larixdecidua

The phenology of sexual reproduction in Larixdecidua Mill, varies from year to year, and some intra- and inter-clonal differences were also found. Megaspore mother cell meiosis occurred at the time of pollination, during the second half of April, resulting in three or four megaspores. The free nuclear stage and cell wall and archegonia formation were completed in late May and the first half of June. An average of four archegonia was observed in each ovule, but the number ranged from two to six. Fertilization occurred during the first 20 days of June, about 7 weeks after pollination. A four-tiered, 16-celled proembryo formed. Meristematic regions formed in the embryo from the end of June to mid-July. Fully developed embryos were observed in mid-August. Simple polyembryony and delayed cleavage polyembryony were observed. Lack of pollination, disturbances during megasporogenesis and female gametophyte development, failure of fertilization, and embryo degeneration are the major factors resulting in empty seed.

Hungarian Historical Portraits

I propose to discuss three letters of Liszt not usually mentioned in connection with the history of the Bungarian Historical Portraits known up to now. In a letter from Budapest written on February 26, 1885, the composer told Olga Meyendorff he had composed some 40 pages of Hunganan music that, month: a rhapsody for the exhibition album (Hungarian Rhapsody No. 18) another rhapsody for his old friend Abranyi (Bunyarian Rhapsody No. 19), a Csardas obstine', and a very funeral march.l While still in Budapest in the first half of April, Liszt also wrote a brief Preludio funebre. One year after the composer's death, the Hungarian funeral march and the piece of funeral music were published by Gollerich through the firm of Breitkopf und Hartel, under the title Tra?bervorspiel und Trcluermarsch; he omitted from the title of the funeral march the word Hungarian, upon which Liszt had laid special emphasis in his letter. This Hungarian funeral march is of course the one upon which Liszt based one of the pieces in the Hunyarian Historicat Portraits. In the first half of June in the same ytsar, Liszt attended two concerts of his own music in Antwerp. From there he wrote on June 8 to the publisher Taborszky in Budapest saying he would send him some short Hungarian piano pieces of his in early July, and orchestrate them at a later date. Their title was Dem Andenken Szechenyi, Deak, Eotvos, Teleki, Vorosmarty, Petofi. Petofi had already been published by Taborszky; Liszt mentioned in the letter that he intended to add a number of closing chords in the new edition. As a seventh piece he proposed adding Mosonyis Trauerklange (Mosonyis Grabgeleit), which Taborszky had likewise published earlier. He wrote that all the new works were ready in a manuscript, and that he only needed z copyist. He would give Taborszky further details about publication when he

Selected bioclimatological characteristics of differently aged successional stages of abandoned fields

The following bioclimatological characteristics were measured on differently aged successional stages of abandoned fields: temperature on soil surface under snow layer, and depth of frozen soil in period of culminating frosts, daily course of temperature in top soil layer; maximum temperature in top soil layer during first half of June. Results are compared with general assumptions about the development of abiotic factors during succession and discussed from the point of view of the ecological theory of stability.

Cyst‐forming Nematodes on Cereals in Bulgaria1

Heterodera avenae and Heterodera latipons are widespread on cereals in Bulgaria and mixed populations are encountered. H. avenae populations reach their highest point on barley after ten years cereal monoculture. The two‐field crop rotation maize/cereals keeps the population at a low level. H. avenae has been found on most cultivars of wheat and barley cultivated in Bulgaria. The author had detected two previously unreported hosts: Agrostis capillaris and Cynosurus cristatus. The most appropriate conditions for infection on cereals occur in April. Nematode development starts in April and finishes in the first half of June. Nematophthora gynophila parasitizes about 20% of the cysts, while Catenaria auxiliary and Lagenidiaceous fungi do so to a lesser extent.

Waterfowl Populations in Eastern Lancaster Sound and Western Baffin Bay

The seasonal distributions of oldsquaws (Clangula hyemalis), common eiders (Somateria mollissima) and king eiders (S. spectabilis) were determined through aerial surveys in eastern Lancaster Sound (1976, 1978 and 1979) and northwest Baffin Bay (1978, 1979). Sightings of geese are summarized in an Appendix. The major spring influx of both eiders occurs about the second week of May but most oldsquaws do not arrive until the first half of June. In spring, all three species are rare in offshore areas, are most abundant along coasts in the northern half of the study area, and tend to depart to nesting areas during the last week of June. Oldsqaws molt along coasts of Lancaster Sound and northwest Baffin Bay, but both species of eiders undertake molt migrations. Three waves of eider out-migration were detected in 1976 and 1978. Distribution and movements within the study area are related to probable migrations routes and ice conditions.Key words: oldsquaw, king eider, common eider, geese, aerial surveys, distribution, molt migration, eastern Arctic, Baffin Bay, Lancaster Sound

Folic acid supplement and intrauterine growth.

The effect of a folic acid supplment on birth weight and placental weight in women delivering in the early summer in Denmark was investigated. Thirty-six women with normal pregnancy and expected delivery in the first half of June were selected consecutively. They were paired two and two, and allotted to two groups, one of which was supplied daily with 5 mg folic acid, and the second with tablets without folic acid, from the 23rd week of pregnancy. A significant correlation was found between erythrocyte folic acid and birth weight. The infants in the folic acid group were 12.7 per cent heavier than those in the control group (p less than 0.01). A similar difference was found with regard to placental weight and the number of placental cells.

Hawthorn powdery mildew: Diurnal and seasonal distribution of conidia in air near infected plants

Conidia of Podosphaera clandestine Lev. were trapped near powdery mildew infected bushes of hawthorn, Crataegus monogyna Jacq., in Leeds, Yorkshire, U.K., during 1972. The highest numbers of conidia were trapped between 11.00 and 16.00 h each day. None were trapped between 24.00 and 06.00 h, with very few being airborne from 18.00 to 24.00 h. First mildew primary infections were observed developing from a few infected buds on 26 April. First conidia were trapped on 18 May, with high numbers being airborne during the first half of June and again (with even higher catches) in the first half of July. The greatest increase in secondary leaf infections occurred also in two peaks, at the end of June and at the beginning of August. Both the early July peak of conidia in the air and the early August increase in mildew infections were related to clipping the infected bushes at the end of June and the infection of newly induced lateral shoots.

Seawater Adaptation and Parr–Smolt Transformation of Juvenile Atlantic Salmon, Salmo salar

Seawater adaptation of 1- and 2-yr-old Atlantic salmon, Salmo salar, presmolts and smolts was assessed during exposure to salinity increasing from 0.1 to 31‰ by examining changes in the osmotic concentration of their serum, urine, and intestinal fluid. Both age-classes adapted to seawater equally well; the marine osmoregulatory mechanisms apparently function before completion of parr–smolt transformation. Adaptation was possible during the parr stage for fish exceeding 12–13 cm fork length. The timing of transformation was synchronous for 1- and 2-yr-old juveniles as demonstrated by changes in their lipid and moisture content and condition factor (K). Condition factor of juveniles at the Mactaquac Hatchery, New Brunswick (45°58′N), decreased from February until the second half of May, while lipid content decreased from February until the second half of June. Migratory activity of juveniles at this location was maximal during the second half of May coincident with attainment of minimum K values and decreased during the first half of June as K values increased. While timing of changes in lipid and moisture content and K values were similar for juveniles at the Mersey Hatchery, Nova Scotia (44°10′N), lipid content of fish at the more southerly station decreased at a greater rate and migratory activity was apparent earlier. This was probably attributable to the advanced temperature cycle at that location. Smolt-release dates are discussed in terms of the development of the marine osmoregulatory mechanisms and the timing of parr–smolt transformation. Key words: Atlantic salmon, seawater adaptation, parr–smolt transformation, migration, hatchery management

Apple, Early Mite Control, 1976

Abstract Test materials were applied to 11-year-old apple trees at Monmouth, Maine, as dilute sprays with a hand gun from a hydraulic sprayer operating at 300 psi and at a rate of ca 500 gal per acre. Spray dates were April 23 (half-inch green). May 10 (pink), June 2-3 (petal fall), June 10 (first cover), and June 24 (second cover). The standard pesticide program consisted of captan 80W.(1.25 lb/100 gal) on 14 dates, Epsom salts (15 lb) and Marlate 50W (3 lb) on June 3, 11, and 24, and Sevin 80W (1.25 lb) on July 8 and 22. There were no tank-mixtures of acaricides with other pesticides. There were 4 single-tree replications per treatment. A randomized complete block design was utilized with 2 Cortland and 2 Early Mcintosh cultivars per treatment in Test 1, 4 Red Delicious per treatment in Test 2, and 2 Mcintosh and 2 Golden Delicious per treatment in Test 3. From each tree, 25 leaves were collected mostly at chest-height around the periphery of the tree, brought into the laboratory, and brushed onto glass plates coated with a Tween 20-alcohol mixture; mites were counted the same day. Mite population pressure was not very severe. Following hot and dry weather the first half of June, there was abundant rainfall through July.

The biology and life cycle of Nemoura avicularis Morton (Plecoptera)

SummaryData are presented on the biology and life cycle of Nemoura avicularis Morton in a North Wales lake, Llyn Dinas, and in the laboratory. Aspects of egg, nymphal and adult biology are described and discussed. Special attention is given to the early instars. The life cycle in the field was followed for a 2‐year period. Eggs hatched during April, May and the first half of June, and growth then continued more or less continuously until late January when the nymphs were fully grown. Emergence, however, did not begin until March, reaching a peak in April and continuing into the early part of May. In the laboratory N avicularis was reared through its life cycle from egg to adult. The results of the present study are discussed in relation to previous research on the biology and life cycle of N. avicularis.

The Ovarian Cycle, Reproductive Potential, and Structure in a Population of the Japanese Lacertid Takydromus tachydromoides

A three year study of a population of Takydromus tachydromoides in central Honshu, Japan revealed that yolk deposition in follicles of juvenile lizards begins in the late spring following their first hibernation, at a body length exceeding 41 mm. Adult females emerge from hibernation with yolked follicles. Oviposition of first year lizards begins in early June, reaches a maximum in July and ends before mid-August. Older females begin oviposition in early May, reach their peak in the first half of June, and cease laying in late July. In experimental lizards corpora lutea regressed from an average of 2.1 mm on the day of oviposition to 1.0 mm five days postoviposition. These persist as corpora albicantia apparently for the life of the lizard. Estimates of age groupings by counts of corpora albicantia suggests that first year females contain none in spring and 4-13 in fall; second year lizards, 1-12 in spring and 14-26 in fall; third year females, 14-23 in spring and 26-39 in fall; and fourth year females, 31-40 in spring and 51-69 in fall. The incidence of corpora albicantia in adult lizards collected from 15 August until hibernation is 97%. Clutch size of first year lizards ranges from 1 to 4 for all clutches, with means of 2.6 for the first clutch and 2.4 for the second and third. Clutches

Ecology of Cladophora in Farm Ponds

The ecology of Cladophora glomerata (L.) Kutzing was studied in five farm ponds near Ithaca, New York, in comparison with a control pond in which the alga was absent. Periodic samples and observations were taken over a 14—month period for temperature, pH, light penetration, water level (including ice and snow cover), nitrate, phosphate, BOD, plankton (counts and identity), and condition of Cladophora glomerata. C. glomerata was found to live throughout the year in the vegetative condition. In the pond which contained the most C. glomerata, ankinetes occurred in abundance throughout the year except in May when a large percentage of them germinated. Approximately 5% of the overwintering vegetative cells in that pond also released zoospores during May and the first half of June. Filaments which overwintered on the bottom began rising to the surface in mid—May, and their vegetative growth during late June and early July caused the greatest increase of the alga. Increase in mass of the alga from germinating akinetes and zoospores was minor compared with vegetative increase from overwintered filaments. Temperature, pH, and phosphate concentration were not directly related to C. glomerata productivity. Amount of light did not limit the abundance of the alga, but decrease in amount of light may initiate akinete and zoospore formation. Plankton counts in the six ponds indicate that each has approximately the same total productivity. High productivity of C. glomerata was directly associated with high nitrate and high biochemical oxygen demand.

Bay of Islands and Humber River Atlantic Salmon Investigations

Humber River is one of the important Atlantic salmon rivers of Newfoundland both from the standpoint of the angling in the river and the commercial fishery at the mouth of the river in Bay of Islands. The fishery was investigated in 1942 and a general survey was made of the main river and its tributaries in 1943 to determine conditions for spawning.The sea-age classes of Bay of Islands salmon and their percentage composition were: 1, 57.2; 2, 32.8; 3, 0.5; and previously spawned, 9.5. The 1 sea-year or grilse class was less numerous in June than 2 sea-year class, but was more numerous during the rest of the season. The 3 sea-year class was not represented at all until August, whereas the previously-spawned class had a higher representation in the first half of June than it did later in the season. According to fishermen's reports, the time of the run of the older salmon is usually from the last week of May to the first week of August with the peak around June 15, whereas grilse are caught from June 15 to the last week in August with the peak during the first half of July.The river-age classes of Bay of Islands salmon and their percentage representation were: 2, 2.1; 3, 42.1; 4, 51.6; 5, 4.0; and 6, 0.1.The average river age was 3.6 years.The average size of grilse was 52.8 cm and 3.4 lb (1.54 kg), and that of the sea-age class 2 was 75.3 cm and 10.6 lb (4.81 kg). Four per cent of the grilse and 28% of older salmon from Bay of Islands contained food; after July 22 no fish containing food was found. Capelin formed the predominant food item, and, almost always, the remainder was fish of other species.A survey of the main Humber River and its tributaries revealed a number of natural obstructions to the passage of salmon. A brief description of these is given, together with some suggestions for improvement. Access of anadromous salmon to Grand Lake and tributaries has been cut off by a dam. The lake now contains lake salmon, brook trout, and Arctic char.

Joint Effects of Maximum Temperatures and Rainfall on Corn Yields, Experiment, Georgia1

SynopsisMaximum daily temperatures and rainfall averaged by 5‐day periods for 18 periods during each growing season of a 38 year span were related to corn yields at Experiment, Georgia, using a set of second‐degree orthogonal polynomials as regression integrals. Results indicated that high temperatures near the end of the growing season are beneficial if rainfall is adequate. High temperatures when no rainfall occurs causes greatest damage in the first half of June. The value of an inch of rainfall declines for a time after the usual planting date and then increases sharply during the later part of the growing season, especially when associated with the higher temperatures which are normal for that period.

Diurnal variation of intermediate and large ions of the atmosphere at Washington, D.C.

Continuous records of the intermediate‐ion and the large‐ion contents of the atmosphere at Washington, D.C., were secured for identical samples of air, during the latter part of May and the first half of June 1933. The results reveal diurnal variations in the two sets of ions that are similar in character. The most prominent features of each is a pronounced maximum centering on about 21h, local time. For the 12‐hour interval, from 4h to 16h, both ion‐contents are low and undergo but minor variations. The variation in the number of intermediate ions from day to day is proportional to the variation in the number of large ions present, but the variation is correspondingly less during times of the higher than during times of the lower large‐ion content of the atmosphere. Intermediate ions are generally numerous during times of thunderstorms, not as a consequence of the Lenard effect, as surmised by Schachl, but probably because of the increased number of small ions present at such times. The increase in number of small ions is apparently due, according to previous results, to radioactive matter carried down by the rain after having been carried upwards from the Earth's surface through convection‐currents during the formation of the thunderstorm. Without further investigational work, the full significance of the similarity in character of the diurnal‐variation curves for intermediate and large ions is not fully apparent, but it appears that particles are coming into the atmosphere, assorted into two definite sizes, from a common source.

Bacteriological Research in Bombay

THE report of the Bombay Bacteriological Laboratory for the year 1914, by Major W. Glen Liston, reached this country recently. The report is divided into two parts: (i) that dealing with plague work, and (2) that dealing with general preventive medicine. Statistics are furnished which tend to show that the uninoculated are attacked three times more frequently than the inoculated (against plague). One drawback to the use of plague vaccines is the severe reaction which follows, deterring others from undergoing the operation. It is now suggested, as results of experiments on rats and observations on man, that a small initial dose of 1–2 c.c. should be given, to be followed in a week by a second dose of 2–4 c.c. It appears that there are two other species of fleas of the genus Xenopsylla—viz., X. brasiliensis and X. astia—besides the originally known species X. cheopis, which, however, forms 80 per cent, of the three species concerned. Whether they all transmit plague is a question which must arise. The results of the examination of rats in the laboratory show that both in the case of M. rattus and M. decumanus there is a rise above the mean in the rate of infection in the latter half of January, whereas the rise above the mean in human plague mortality occurs in the first half of March. The fall below the mean occurs at the same time for both species of rats and for man—viz., in the first half of June. The summit of the infection for M. rattus precedes that of M. decumanus by a fortnight, while the infection of the latter and the mortality in man reach their maximum at the same time—viz., in the latter half of April.