The present paper deals with a further nine species of Diaspinae which are new to science. I desire to express here my sincere thanks to Mr. E. E. Green for his invaluable assistance in working out my material.

The frequency of defecation in relation to constant0/simulated outdoor temperatures and larval age (instar) was examined under laboratory conditions in four species of pine sawflies (Diprionidae): Gilpinia frutetorum (Fabricius), Diprion pini (Linnaeus), D. similis (Hartig) and Macrodiprion nemoralis (Enslin). Defecation interval and total faecal production was regular under higher constant temperatures (higher production in younger instars, second and third) and production significantly decreased under varying air temperatures during the same period (24 hours) when larvae of younger instars were influenced more by lower temperatures. The influence of larval age (instar) on faecal production was insignificant if larvae were exposed to varying temperatures during 24 hours. Faecal production and temperature were positively correlated in each of the four species and instars tested, as well as in total (all the test species and instars combined). Implications of the results for estimating canopy larval density by frass-drop measurements in the field are briefly discussed.

Despite the continued efforts on the search for different genotypes, Capsicum annuum (L.) is quite susceptible to attack by pest arthropods, especially the broad mite Polyphagotarsonemus latus Banks. Thus, the host preference, population growth and the injuries assessment of P. latus was studied on six C. annuum genotypes used in Brazil (Atlantis, California Wonder, Impact, Palloma, Rubia and Tendence). Host preference was accessed in choice tests, pairing the several genotypes, and the population growth was observed through non-choice tests in laboratory. The injuries assessments were evaluated in the greenhouse, comparing the injury level among the six genotypes. The results indicate that California Wonder and Palloma genotypes were more preferred by P. latus, and Impact and Tendence were less preferred. P. latus presented positive population growth rates (ri) on all the genotypes, however, Palloma and California Wonder showed the highest values of population growth rate (ri = 0.344 and ri = 0.340, respectively), while Impact had the lowest value (ri = 0.281). All the evaluated C. annuum genotypes showed low tolerance to P. latus and exhibited several injuries, but there was no statistical difference between them. California Wonder had the highest average number of mites/leaf (57.15), while Impact and Tendence obtained the lowest values (36.67 and 35.12, respectively) at the end of the evaluation period. The total average of injuries notes at the end of the bioassay did not differ between the genotypes. The number of mites/leaf was growing for the injury scale to the note 3.0, but when the injury scale approached the note 4.0, there was observed a decrease in the number of mites/leaf for all the genotypes.

Eriophyes carinatus, Green, is commonly known as “ Purple Mite ” in Ceylon. It was first described by Green under the name of Typhlodromus carinatus, the generic name subsequently becoming Phytoptus, and finally (up to the present time) Eriophyes.

An original method of breeding Phlebotomus papatasii (Scop.) in the laboratory in the Egyptian climate was evolved, whereby the development of a fungal growth, a well-known obstacle, was prevented by incorporating, in the larval feeding medium, living material from cultures of a bacterium, Alcaligenes viscosus, which had been found to be the predominant micro-organism in samples of soil collected from breeding places of P. papatasii in the field. Later, eight other Schizomycetes were also found to keep in check the development of mould. Certain fungicides also gave satisfactory results. Breeding pots made of unglazed earthenware were used. A layer of finely sieved sand (18 meshes) about 5 cm. deep was placed at the bottom of the pot and moistened with sterile water. To a mixture of one part dried, ground, sieved guineapig faeces (60 meshes) and two parts sieved dry earth (60 meshes), sufficient of a water suspension of the bacterium was added to impart a damp but friable condition. Granules of this larval feeding medium were then scattered over the sand in a loose layer about 1 cm. thick. Each breeding pot was stood in a petri dish of water and was placed in a small muslin cage to which adult insects were introduced. The females, which obtained their blood-meals from three-day-old white mice, oviposited within the pots, and no eggs were laid elsewhere. Development from egg to adult was completed successfully in this medium, and a healthy culture of the insect was maintained in the laboratory for several years.

Some months ago I received from Dr. Guy A. K. Marshall, Director of the Imperial Bureau of Entomology, London, a collection of termites from Ceylon which he kindly entrusted to me for the purpose of identification. The termites were collected by the Government Entomologist of Ceylon, Mr. T. C. Hutson, in different parts of the island, in tea plantations. If this is the case, the termites were presumably not collected on the plains but at some height above the sea-level, where tea preferably is cultivated. There are, however, no detailed records of the height of the localities.

The paper includes a description of studies on Anopheles gambiae Giles in the insecticide-free Umbugwe area of Tanganyika, and the results of dissections of A. gambiae and A. funestus Giles for sporozoite infections.

The densities of A. gambiae and A. funestus were assessed in houses by pyrethrum spray catches in 90 houses distributed in ten villages in the Umbugwe area between March 1960 and February 1962. A. gambiae was seasonally abundant, a sharp increase in density being associated with periods of rain. A. funestus type form was scarce in houses throughout the year, although a larval survey showed it to be the most common member of the complex of A. funestus in the area.

The average ratio of fed to gravid individuals of A. gambiae was 2·3:1 from June 1960 to November 1961, with peaks reaching 7:1 in March 1960 and 7·5:1 in January 1962. The peaks were attributed to rapid increase in production of adults during the limited period of the rainy seasons that followed very dry conditions.

Thirteen per cent, of recently fed individuals of A. gambiae were found in the exit window traps of experimental huts, having attempted to leave the huts on the night of feeding.

Two distinct types of huts are commonly found in the area, the tembe, which is large, divided into an average of five rooms by walls that are usually incomplete at the top, and accommodates large numbers of cattle as well as humans; and the banda, which is smaller, divided only into two rooms and seldom housing any domestic animals. Precipitin tests showed that whereas only 20 per cent, of individuals of A. gambiae taken in tembe had fed on man, in banda huts the percentage was 77. It was also shown that there was a dispersal of A. gambiae within a hut shortly after feeding. In a tembe. one-third of the individuals positive for man, and one-quarter of those positive for cattle had moved to rooms other than those in which they had fed.

A sporozoite rate of 1·47 per cent, was found among 3,746 specimens of A. gambiae dissected. Of the total number of 55 sporozoite-positive females of A. gambiae, 39 were found among the 424 individuals dissected in February 1962, thereby indicating unusually heavy transmission during the early part of 1962. A. funestus type form appeared to be of virtually no importance in malaria transmission in the Umbugwe area. Transmission by A. gambiae was highly seasonal, for although the percentage of gland-positive specimens was slightly higher in the long dry season than in the rainy season, the much larger mosquito population in the latter led to a higher number of infective bites in the rainy seasons. The highly seasonal transmission by A. gambiae was reflected in the results of examination of blood-films of people attending the Government dispensary.

In the course of entomological investigations of the rubber-producing plants, Scorzonera tau-saghyz, Lipsch. & Bossé, Taraxacum kok-saghyz, Rodin, and Taraxacum megalorhizon, Hand.-Maz., at the Ukrainian Rubber-Plants Experimental Station (near Kremenchug), it was discovered that the destruction of these plants can be caused by root Aphids and the ants associated with them.

Over the last 40 years, many types of population genetic markers have been used to assess the population structure of the pest moth species Helicoverpa armigera. While this species is highly vagile, there is evidence of inter-continental population structure. Here, we examine Z-chromosome molecular markers within and between Chinese and Australian populations. Using 1352 polymorphic sites from 40 Z-linked loci, we compared two Chinese populations of moths separated by 700 km and found virtually no population structure (n = 41 and n = 54, with <1% of variation discriminating between populations). The levels of nucleotide diversity within these populations were consistent with previous estimates from introns in Z-linked genes of Australian samples (π = 0.028 vs. 0.03). Furthermore, all loci surveyed in these Chinese populations showed a skew toward rare variants, with ten loci having a significant Tajima's D statistic, suggesting that this species could have undergone a population expansion. Eight of the 40 loci had been examined in a previous study of Australian moths, of which six revealed very little inter-continental population structure. However, the two markers associated with the Cyp303a1 locus that has previously been proposed to be a target of a selective sweep, exhibited allele structuring between countries. Using a separate dataset of 19 Australian and four Chinese moths, we scanned the molecular variation distributed across the entire Z-chromosome and found distinct blocks of differentiation that include the region containing Cyp303a1. We recommend some of these loci join those associated with insecticide resistance to form a set of genes best suited to analyzing population structure in this global pest.

The following is an account of the continuation of experiments and observations carried out in connexion with an investigation into the ecology and control of pine beetles, with special reference to Myelophilus piniperda and M. minor.

A simple optical method for automatic recording and classification of a suction trap catch is described. The insects are illuminated against a dark background as they pass through a detection volume, and the amount of scattered light is used to measure insect size. The design centres on the detection volume, which is a volume through which the insects are made to pass, and within which they may be detected. The design is approached in four stages: 1. Delivery of insects to the detection volume. 2. Illumination of the detection volume. 3. Collection and detection of scattered light. 4. Signal analysis. The analysis could also be applied to related techniques. Results with a prototype demonstrate that classification into broad size categories is straight-forward (e.g. approximately three classes spanning body lengths of 2–7 mm), despite uncertainties of insect reflectivity, aspect and trajectory. Applications of the method are discussed, along with a brief mention of alternative techniques.

A method for physiological age determination in blackflies is described from studies on Simulium equinum (Linnaeus), S. ornatum Meigen, S. erythrocephalum (De Geer), and S. nigrum (Meigen) in Russia, and S. vittatum (Zetterstedt), and S.verecundum-venustum supercomplex in Canada. The method uses neutral red to stain the ovariolar structures which indicate preceding gonotrophic cycles. Two different processes can occur in the ovariole during the gonotrophic cycle: egg development with ovulation, or degeneration of a terminal follicle. Egg-sacs are resorbed and form zones of granulation which accumulate in the ovariole at each gonotrophic cycle. Following degeneration of the terminal follicle, a follicular relic (═gonotrophic dilatation) forms. The sum of zones of granulation plus follicular relics in each ovariole can indicate the number of completed gonotrophic cycles. However the number of follicular relics alone does not correspond to the number of preceding gonotrophic cycles and cannot reliably be used for determination of the parity of a female. Female flies collected in nature were categorized as: nulliparous; 1-parous; or multiparous. In multiparous females, most ovarioles have no more than two zones of granulation or a combination consisting of one zone of granulation and a follicular relic. Females in this category are considered to be 2-parous. In some ovarioles of parous females the germarium and terminal follicles were found to have disappeared.

Epidinocarsis lopezi (De Santis) was found to parasitize and complete development in all developmental instars of its host, Phenacoccus manihoti Matile-Ferrero. However, parasitoid mortality was high (15·8%) when development took place in the first nymphal instar of the host. Complete development from egg to adult emergence was prolonged in smaller hosts, and developmental periods recorded were 18·8, 17·4, 16·1 and 14·9 days for the first, second, third and fourth nymphal instars, respectively. Irrespective of the age of the host parasitized (with which size is strongly correlated), E. lopezi completed only one life-cycle during one life-cycle of P. manihoti. Oviposition commenced within 24 h of emergence and lasted effectively for six days, during which 95% of its eggs were laid and 10·8 large hosts were killed through host feeding. Unmated females of E. lopezi are arrhenotokous, laying only male eggs; eggs laid by mated females produced males and females in the ratio of 1:3 in favour of females.

The following notes are based on material submitted to me for study by the Imperial Bureau of Entomology. The drawings were made by Mr. D. E. Kimmins.

Hispaniella africana sp. n. is described from material reared from Inchoaspis dentilobis (Newst.) (Horn., Diaspididae) attacking Sapium ellipticum (Euphorbiaceae) in Uganda. This is the first record of the genus from tropical Africa.

During the course of plague investigations carried out in Kenya Colony in 1921 by the late Dr. R. Van Someren, and in Uganda during 1922 by the same collector in conjunction with Dr. C. A. Baker, some hundreds of Mallophaga and Anoplura were collected, mainly from small rodents. This material was sent to the Imperial Bureau of Entomology in two instalments, and the present paper deals only with a new species and variety represented in the first collection forwarded by Mr. T. J. Anderson, Government Entomologist, Nairobi. The rest of the collection will be dealt with later. The opportunity has been taken to add also the description of a very remarkable louse which infests an Indian tree shrew.

An outbreak of body lice might require several control measures according to circumstances. Two types of fumigant action have been investigated in the laboratory and the field :—

(1) House fumigation for disinfesting typhus-contaminated premises.

Lice were fairly similar to bed-bugs in their resistance to the fumigants tested. In practice, 16 oz./l,000 cubic feet of hydrogen cyanide will kill lice and eggs : 2 lb. of sulphur/1,000 cubic feet is also successful if the wind is not strong.

(2) Bin fumigation of garments by saturated vapours.

The saturated vapours of solids such as naphthalene and paradichlorbenzene are extremely slow in action ; even with 20 hours exposure at 20°C. they are unreliable. Liquids such as heavy naphtha or trichlorethylene are much more promising.

For reading and criticising this paper I am grateful to Professor Buxton in whose department the work was done. My thanks are also due to the Medical Research Council for a grant.

In plot trials with seed dressings on late-sown oats against shoot attack by frit fly, Oscinella frit (L.), chiefly near Cambridge, England, γ BHC, parathion, dieldrin, heptachlor, Rogor and WL 1650 (Telodrin) (1,3,4,5,6,7,8,8-octachloro-3a,4,7,7a-tetrahydro-4,7-niethanophthalan) (dry and wet) reduced the attack but the effect was variable and for the most part not appreciable.

In 1952 and from 1956 to 1960, trials were made on the effect of late sprays of various insecticides applied to late-sown oats when symptoms of frit-fly attack were already conspicuous and sometimes severe. An advantage of this type of treatment over preventive sprays is that it ensures that the treatment is applied only where and when necessary. Single sprays of parathion, dieldrin, γ BHC and Rogor prevented or markedly reduced further attack and they were most effective when applied within about 15 days of the beginning of egg-laying and when plants were in the young seedling stage. Compared with the best treatment of two early preventive sprays of DDT there was only a slight reduction in yield. Parathion and to lesser extent γ BHC killed many larvae inside the shoots and probably prevented others from entering the shoots.

Field studies in Zimbabwe elucidated the responses of Glossina morsitans morsitans Westwood and G. pallidipes Austen to natural and artificial trunks of trees baited with odours of acetone, 1-octen-3-ol and phenols. The numbers of tsetse electrocuted in flight near the base of the trunk increased 2–12 times when the trunk was shortened from 7.2 m to 0.9 m and its diameter was increased from 25 cm to 5 m, when the base was coloured blue or black to contrast with the upper trunk, or when the upper trunk was separated from the base by a gap of 2.7 m. A swarm flying near short trunks was more compact than near tall trunks. Electrocuting grids to catch alighting tsetse indicated that only about 20% of the attracted tsetse alighted on the base of the trunk, whether this was blue or blue/black. Since there is presently no apparent means of cost-effectively avoiding the inhibitory effects of tall trunks, the use of odour-baited trees as baits for tsetse control seems uneconomical.

When carrying out an investigation into the mosquitos of New Zealand, * the writer found that a very common species bred in saline and semi-saline pools above high water mark along the rocky parts of the North Island coast line. For some time it was considered that this mosquito was unrecorded, but it appears that Hutton described it as a Tipulid under the name Opifex fuscus.† This was pointed out to me both by Mr. G. V. Hudson, of Wellington, who is in possession of Hutton’s Tipulid types and had seen the illustrations here reproduced, and later on by Mr. F. W. Edwards, of the British Museum, who published a short account of the insect from material recently sent to him by Mr. Hudson.‡