THE ENUMERATION OF WATERBORNE BACTERIA BY A NEW DIRECT COUNT METHOD

SUMMARY: A direct method has been devised to enumerate bacteria in lake water, using a concentration technique. The method involves the staining of 10⁻² ml samples of water with gentian violet dissolved in a glycerol-water base, and concentrating in vacuo . The residue remaining after concentration consists of glycerol and stained bacteria. Glass capillaries are filled from the concentrate and the volume of the contents determined. The organisms in this are counted microscopically. Results by the direct count were from six times to eleven thousand times greater than by the colony count.     

Fatty Acid and Isoprenoid Quinone Composition in the classification of Bacteroides melaninogenicus and Related Taxa

Aerobic deterioration of lucerne, maize and wheat silages was characterized by rapid increases in yeast and mould flora which oxidized lactic and volatile acids resulting in increased temperature and pH. While populations of yeasts and moulds were similar, temperature increases were slightly greater for silages inoculated with Lactobacillus acidophilus and Candida spp. After 48 h the pH of the inoculated silages was higher in general and concentrations of acids were lower than controls. Bacterial growth was slight although continued lactic acid production was probable. In contrast to lucerne and maize silages, the pH of wheat silage remained stable during this period because of high butyric levels, but temperature and yeast populations increased. After 48 h the pH rose above 5 in maize and lucerne, and bacterial growth and metabolic activity resumed resulting in volatile and non-volatile acid production from carbohydrate fermentation and deamination of amino acids. During this phase of aerobic deterioration yeast growth slowed or stopped, but temperatures remained high and pH continued to climb probably because of production of ammonia. The changes in gross composition of the silages did not follow any particular pattern. Losses in dry matter were small (2.5–4.0%) and changes in individual components probably reflect this loss rather than substantial changes. Protein availability in the lucerne silages undoubtedly decreased, as protein losses were high. It is concluded that the aerobic deterioration of silage is enhanced by the addition of L. acidophilus and Candida spp. at ensiling.     

Carbonyl Compounds Produced by Cryptomonas ovata var. palustris*

SYNOPSIS. Some neutral carbonyl compounds synthesized by Cryptomonas, ovata var. palustris were identified as methanal, ethanal, 2-propanone, pentanal, and heptanal by means of thin-layer chromatography, gas chromatography and infrared spectroscopy.     

Molecular phylogeny and generic‐level taxonomy of the widespread palaeotropical ‘Heteropsis clade’ (Nymphalidae: Satyrinae: Mycalesina)

The mycalesine butterfly genus Heteropsis Westwood, 1850 (Satyrinae: Mycalesina) has recently been conceived to be represented in three major palaeotropical regions (Madagascar, Africa and Asia), but there has been no formal taxonomic treatment covering this entire group. Studies aimed at understanding the evolutionary success of Mycalesina in the Old World tropics have been hampered by the lack of both a robust phylogeny and a stable nomenclature for this satyrine subtribe. Here, we present a well‐supported molecular phylogeny based on 10 genes and 133 exemplar taxa, representing almost all known species groups of Heteropsis (s.l.), and including all but four known species in Madagascar. We also combine sequences of the exemplars with a morphological matrix of 428 characters. The widespread ‘Heteropsis clade’ is confirmed as monophyletic, but lineages in different geographic regions also form endemic and well‐supported clades with deep divergences among them. Here we establish this group as comprising three genera, Heteropsis (Malagasy region only), Telinga Moore, 1880 (Asia), and Brakefieldia gen.n. (Africa). We recover the genera Telinga and Brakefieldia as sisters with high support. Each genus is taxonomically characterized and a revised synonymic checklist is appended with new combinations and some changes in rank. With a well‐resolved topology and updates to the taxonomy of the group, researchers are now in a position to explore the drivers of the spectacular radiation of the group, notably in Madagascar, where the highest phenotypic and species diversity occurs. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:AAF9F440‐A2D6‐4483‐BF35‐9BC074D9D29B .     

Observations on the foraging activity of Hospitalitermes umbrinus (Haviland), (Isoptera: Termitidae) in the Gunong Mulu National Park, Sarawak

Abstract. 1. A single nest of the black surface-foraging nasute termite Hospitalitermes umbrinus was studied for 5 days in July 1978. Foraging parties of workers and soldiers tend to leave the nest in a continuous stream in the evening and return carrying food balls during the following morning.
2. An estimated maximum of 500000 individuals were involved in the foraging excursions. At a density of 3 nests ha^-1, the total foraging population is estimated as being at least 180 m^-2.
3. The colony brought back an estimated 46.4 g (d.w.) of food in 4 days. The biomass of the colony was estimated at 349 g (d.w.) ( c. 1396 g w.w.) excluding alates and the consumption at 8.3 mg (d.w.) g^-1 (w.w.) d^-1.
4. The food balls were found to be of two types, light and dark coloured. The light balls contained wood constituents, bryophytes, blue-green algae and fungal hyphae while the dark balls consisted mainly of lichens and their spores.
5. Swarming began at 14.30 hours on 9 July and ended with the nuptial flight at 17.32 hours. About 3000 alates were released. They climbed to 9 m on a tree before taking off.