The chief aims of the survey and an important conclusion reached during some preliminary work are briefly stated. This latter was the recognition of two distinct nest types—the wet nest, exposed to rain, and the dry nest, sheltered from rain.The methods used to examine materials and record results are described. They were closely similar to those described in a previous publication.The insect fauna is listed under three headings: (a) ectoparasites of birds, which includes 12 species; (b) scavengers, including 66 species; and (c) predators, comprising 14 species. Figures are given for the frequency of occurrence and the abundance of the more important nidicole species, abundance being given as an arbitrary estimate. The importance of each as a pest is also briefly stated, and detailed records are given for uncommon or particularly interesting species.The mite fauna is dealt with in a similar manner. It includes one ectoparasite, 10 scavengers and 11 predators.The basic composition of nests and the temperature and humidity conditions within them are described briefly and the possible influence of these factors upon the nest fauna is discussed.The species of the dry nest community are classified, according to their feeding habits, as ectoparasites of birds, scavengers and predators, and according to their status in the nest, as regular, occasional and incidental inhabitants. The distribution of the group of species which truly characterises this community is discussed.

No abstract

SUMMARY. A number of stored product and domestic insect pests have been recorded from birds' nests. Nests of five species of house‐nesting birds were examined during the first three months of 1950. The composition of the nests is given. An extensive insect fauna was found, including, in particular, clothes moths, house moths and carpet beetles. The mite fauna included species found on stored products. The nature of the environment provided by a sparrow's nest is discussed. Three successive phases are recognizable, characterized respectively by (i) ectoparasites of birds, (ii) a fauna of stored products pests and their predators, and (iii) a humus fauna. The second phase is the one chiefly studied in this paper. While the complete fauna showed considerable variation from one nest to another, the dominant species formed a distinct group which was normally present in every nest. This group consisted of the moths, Tinaea columbariella and Hofmannophila pseudospretella, the beetle, Anthrenus verbasci, and the mites. Mealia pteronyssina. Glycyphagus domesticus and Acaropsis docta.

Hofmannophila pseudospretella is widely distributed in this country. It is a minor pest of stored foodstuffs, clothes and furnishings, and under certain conditions may give rise to a major infestation.The egg stage is characterised by a high sensitivity to temperature and almost complete indifference to humidity. The incubation period varied from 110 days at 10°C. (90 per cent. R.H.) to 8·5 days at 27°C. (90 per cent. R.H.) and from 9·8 days at 90 per cent. R.H. (25°C.). to 14·0 days at 8·5 per cent. R.H. (25°C.). The percentage survival was greatly reduced both at very low (<3 per cent. R.H.) and at very high (100 per cent. R.H.) humidities. The survival of eggs from a single female varied from 56 to 97 per cent. under favourable conditions.The duration of the feeding larval stage varied between 145 days at 13°C. and 71 days at 25°C. (at 90 per cent. R.H. on middlings). Larvae failed to mature below 80 per cent. R.H. at all temperatures. Larvae were reared successfully on a wide range of diets of both animal and vegetable origin, some predominantly carbohydrate, some almost entirely protein. The most rapid development occurred on dead adults and the slowest upon leather and yeast.Under most conditions fully grown larvae entered diapause. This was characterised by a diapause moult after which the larvae assumed a typical diapause appearance. The length of the diapause was extremely variable and was determined largely by the temperature during larval growth. Larvae grown at low temperature did not enter diapause when incubated at 25°C. as fully grown larvae. The diapausing larvae were remarkably resistant to desiccation.The duration of the pupal stage is affected by temperature but not by humidity. It lasted 98 days at 10°C. and 13 days at 28°C.The total length of the developmental period was highly variable because of the variability in the length of the diapause under constant conditions. When the conditions throughout were 25°C. and 90 per cent. R.H. the total developmental period varied between 152 and 266 days, and at 20°C. and 90 per cent. R.H. the figures were 192 to 440 days. The developmental period was approximately 12 months under field conditions.Under crowded conditions, mating was observed between males of H. pseudospretella and females of Endrosis lactella but none of the eggs developed.The weight of the female at emergence was the most important factor governing the number of eggs laid. Weight of females varied between 8·2 mg. and 43·6 mg. and the egg number between 106 and 657 at 25°C. and 70 per cent. R.H. The number laid was significantly reduced at lower temperatures (10°C.) and at lower humidities (20 per cent. R.H.).The sex ratio was found to be approximately 1:1, with a slight predominance of females.The longevity of the fertilised adult female depended upon its weight at emergence and upon the physical conditions. Variation in weights of males was small, and the length of life of mated males could be correlated directly with the physical conditions. The mean longevity of mated females of all weights was 11·9 days at 25°C. and 70 per cent. R.H., 19·0 days at 15°C. and 70 per cent. R.H. and 9·4 days at 25°C. and 20 per cent. R.H. At 25°C. mated males lived 7·1 days on the average, and 18·8 days at 15°C.The only important predator was the mite, Cheyletus eruditus, which destroyed numbers of eggs and young larvae.

This work was undertaken as a supplement to a laboratory study of the lifehistory and behaviour of Anthrenus verbasci (L.) which is being carried out by Mrs. Gr. M. Blake of the Pest Infestation Laboratory. Its purpose was to provide information upon which control measures might be based.-Throughout this investigation attention was paid to the two other common species of Anthrenus-A. fuscus 01. and A. museorum (L.)-and a comparison was made between these species and A. verbasci.Two factors are of obvious importance when considering distribution-the natural geographic range of the species, determined by climatic factors, and the locality distribution, determined by the occurrence of the preferred habitat. Three survey methods were used to study these points-the collection of adults from flowers during May, June and July; the collection of larvae from natural habitats (certain birds' nests, under the bark of trees, etc, of. Woodroffe, 1953); and the inspection of infested premises. These investigations also yielded a considerable amount of information on the field habits of the three species concerned. Collection of Adults from Flowers.