THE FOOD AND REPRODUCTIVE CYCLES OF THE CENTIPEDES LITHOBIUS VARIEGATUS AND LITHOBIUS FORFICATUS IN A YORKSHIRE WOODLAND

Lithobius variegatus and L. forficatus occupy similar ecological niches and frequently occur together although there are differences in their distribution in the British Isles. An investigation of their food and reproductive cycles, being a preliminary step towards a further understanding of their ecological relationships, is described.
Lithobiomorph centipedes have hitherto been regarded as wholly carnivorous, but it is shown that these species feed on litter as well as small litter animals, the presence of litter in the guts of these species not being connected with the presence of animal remains. Whereas L. forficatus takes litter throughout the year, L. variegatus does so mainly in the winter.
Both species appear to lay eggs for a considerable part of the year, though there appears to be only a short period of sperm transfer in spring. It is suggested that the long oviposition period may prevent the loss of the entire brood in a dry summer. The succession of epimorph stadia in L. variegatus is described.
L. forficatus was more common than L. variegatus in the drior part of the woods studied.     

THE MALAYAN WHISKERED FLYING SQUIRREL PETINOMYS GENIBARBIS MALACCANUS

A specimen of the Malayan whiskered flying squirrel Petinomys genibarbis malaccanus (Thomas) is described, with notes on its habits and behaviour in captivity.     

THE IMMATURE STAGES AND AFFINITIES OF THE TACHINID FLY GLAUROCARA FLAVA, A PARASITE OF THE AFRICAN BUSH-CRICKET HOMOROCORYPHUS NITIDULUS VICINUS

Observations are given on the parasitism of Homorocoryphus nitidulus vicinus (Walker) by the African tachinid fly Glaurocara flava Thomson, and the hitherto unknown immature stages of G. flava are described and illustrated. The female of G. flava is shown to be larviparous, producing abundant highly specialised planidium larvae very closely resembling those of the little-known tribe Ormiini. The systematic affinities of Glaurocara are briefly discussed and it is suggested, in view of the reproductive habits and the structure of the first instar larvae, that this genus must be very close phylogenetically to the Ormiine Tachinidae.     

THE DIET OF SOME SINGAPORE ANURA (AMPHIBIA)

Six species of anurans were studied representing four of the five anuran families occurring in Malaya and Singapore. Food items, variation in the diet, and the relationship between predator and prey size are discussed. Singapore anurans show various degrees of selectivity for particular types of prey. In general, availability of prey in the habitat, the size of the prey animals and the size of the predators, especially the gape of the mouth, determined the diet.     

REPRODUCTION AND BREEDING FLUCTUATIONS IN HYDROCENA MONTEROSATIANA A MALAYAN LIMESTONE ARCHAEOGASTROPOD

The reproductive system of Hydrocena monterosatiana Godwin Austen & Nevill, is described and is simpler in construction than those of other Neritacea. Evidence of fluctuating reproductive condition is given although breeding appears to persist throughout the year. Breeding fluctuations are related to changes in rainfall and their nature is compared with taht in other gastropods from the same locality.     

The head anatomy of Epiophlebia superstes (Odonata: Epiophlebiidae)

The relic dragonfly family Epiophlebiidae is recovered as sistergroup of Anisoptera (= Epiprocta) by most molecular and morphological analyses. However, in a recent study it was placed within Anisoptera as sister group of Cordulegastridae. In another study, several affinities to Zygoptera in the morphology of the ovipositor and the egg-laying behaviour were pointed out. Here, we present a detailed study of the outer, as well as the inner, head morphology of Epiophlebia superstes. Compared with the last detailed literature account, three additional mandibular muscles were discovered, as well as additional buccal and pharyngeal muscles. The results are compared with the anatomic features of Zygoptera and Anisoptera. A formal character evaluation focused on head characters confirms the sistergroup relationship of Epiophlebiidae and Anisoptera.     

Considerations for Group Testing: A Practical Approach for the Clinical Laboratory

Group testing, also known as pooled sample testing, was first proposed by Robert Dorfman in 1943. While sample pooling has been widely practiced in blood-banking, it is traditionally seen as anathema for clinical laboratories. However, the ongoing COVID-19 pandemic has re-ignited interest for group testing among clinical laboratories to mitigate supply shortages. We propose five criteria to assess the suitability of an analyte for pooled sample testing in general and outline a practical approach that a clinical laboratory may use to implement pooled testing for SARS-CoV-2 PCR testing. The five criteria we propose are: (1) the analyte concentrations in the diseased persons should be at least one order of magnitude (10 times) higher than in healthy persons; (2) sample dilution should not overly reduce clinical sensitivity; (3) the current prevalence must be sufficiently low for the number of samples pooled for the specific protocol; (4) there is no requirement for a fast turnaround time; and (5) there is an imperative need for resource rationing to maximise public health outcomes. The five key steps we suggest for a successful implementation are: (1) determination of when pooling takes place (pre-pre analytical, pre-analytical, analytical); (2) validation of the pooling protocol; (3) ensuring an adequate infrastructure and archival system; (4) configuration of the laboratory information system; and (5) staff training. While pool testing is not a panacea to overcome reagent shortage, it may allow broader access to testing but at the cost of reduction in sensitivity and increased turnaround time.     

A POPULATION STUDY OF AN EQUATORIAL LAND SNAIL, LIMICOLARIA MARTENSIANA (ACHATINIDAE)

Near the equator in Uganda, the herbivorous land snail, Limicolaria martensiana , occurs in well-defined populations. These populations may be very large and the snails may in places occur at exceedingly high densities. The snails breed all the year round, but with two peaks that correspond with the two annual dry seasons. They enter dispause whenever the weather is very dry. The size of adult snails seems environmentally determined and it varies in different populations : the largest snails occur on soil rich in calcium. The shells of the snails are highly variable and polymorphic in colour and pattern. In particular, there is a streaked form that occurs in all populations, and four distinct pallid "dilute" forms. The relative frequency of the forms varies markedly in different populations. Polymorphism is greatest at high population densities and the snails are all streaked where they are rare. Polymorphism can be distinguished in Pleistocene fossil populations.