A description is given of the detection of an active breeding place of A. mauritianus in the Kurdani River, near Acre. This species was first reported by Barraud in 1920 as breeding in the swamps of the Kishon and Auja. Since that time neither Buxton nor the other workers in Palestine have been able to find this species. It is conceivable that the reason for the failure is due to the fact that the larvae closely resemble those of A. hyrcanus and that like it, the adult is a swamp feeder and not a house visitor.

The material, upon which these observations were made is contained in the collection of the “Centraal Militair Geneeskundig Laboratorium” in Weltevreden (Java). To complete my observations many specimens in the collection of the British Museum were studied and compared.

Q.—Length (12 specimens) 9·5 to 12 mm.; width of head 3·5 to 4·4 mm.; width of front at vertex just under 0·5 to just under 0·6 mm.; length of wing 7·75 to 9·8 mm.

In the American continent, the sugarcane borer Diatraea saccharalis (F.) is the main pest in sugarcane producing areas. The objective of this study was to assess the effect of crop residue management on damage by D. saccharalis, its egg parasitoids and the ants associated with sugarcane. The study was carried out during 2011–2012, 2012–2013 and 2013–2014 crop cycles, in three commercial fields located in different regions of Tucumán state, Argentina. Two types of crop residue management (= treatments) were compared: conservation of trash at the soil surface (CT) and trash burning (TB). In ‘trash conservation’ treatment, crop residue was allowed to remain over the soil surface during the whole sugarcane growing season, while the second treatment consisted of complete burning of trash blanket approximately 2 weeks after harvest. The injury level was measured by recording the number of stalks bored and internodes bored. Parasitism was estimated by counting the total number of eggs and number of black eggs (which indicates the occurrence of egg parasitoids). Ants (Formicidae) richness was calculated by two estimators; abundance-based coverage estimator and incidence-based coverage estimator, using the non-parametric richness estimators: Chao 2 and Jackknife. Finally, the indicator value was estimated through the measurement of specificity and fidelity. In all the parameters studied no significant difference was found between TB and CT treatments.

The prediction of the post-diapause emergence is the first step towards a comprehensive decision support system that can contribute to a considerable reduction of pesticide use by forecasting a precise spraying date. The cumulative field emergence can be described as a function of the cumulative development rate. We investigated the impact of seven constant temperatures and five light regimes on post-diapause development in laboratory experiments. Development rate depended significantly on temperature but not on photoperiod. We therefore fit non-linear thermal performance curves, a better and more modern approach over past linear models, to describe the development rate as a function of temperature. The four parameter Brière function was the most suitable and was subsequently applied to temperature data from 36 previous pea fields, where pea moth emergence was measured with pheromone traps in Northern Hesse (Germany). In order to describe the variation in development times between individuals, we fit five nonlinear distribution models to the cumulative development rate as a function of cumulative field emergence. The three parameter Gompertz model was selected as the best fitted model. We validated the model performance with an independent field data set. The model correctly predicted the first moth in the trap and the peak emergence in 81.82% of cases, with an average deviation of only 2.00 and 2.09 days respectively.

In 1939 I dealt with two species of Ephialtes which parasitise the codling moth, Cydia pomonella, L., namely E. caudatus, Ratz., and E. crassiseta, Thoms., and showed how they differed from E. punctulatus, Ratz. (=extensor, Tasch.) with which species they had formerly been confused. During 1940, F. J. Simmonds, of the Imperial Institute of Entomology, sent to the British Museum a series of a species of Ephialtes bred from this same host in the south of France. This is a new species, and it was previously known to me only from a single female which had been bought by D. S. Wilkinson from O. Schmiedeknecht, who had incorrectly named it Pimpla roborator, F. In fact, this new species does not belong to the same species group as Ephialtes (Exeristes) roborator, F., Grav. (=Pimpla roborator, F., Schmied.), which is a well-known parasite of the European Corn Borer (Pyrausta nubilalis, Hb.) and also parasitises many other hosts.

As there has been considerable confusion in the synonymy and interpretation of E. roborator, F., it seems advisable to give notes on the relevant type specimens seen by me. It has been impossible to find the type of Ichneumon roborator, F. Gravenhorst's interpretation of this very variable species has therefore been taken. The description given by Schmiedeknecht in his Opuscula Ichneumonologica is adequate for the recognition of the female ; the male is very distinct, having a tubercle in the middle of the clypeus, a character unknown in any other described European species. Pimpla cicatricosa, Ratz., which is given by Schmiedeknecht as a synonym of P. roborator, F., is a distinct species.

In connection with further experiments concerned with the significance of the pH of natural and other waters and the relative suitability or unsuitability to the development of the larvae of certain mosquito species, electric currents have been used to alter the pH readings, thus avoiding the necessity of adding extraneous acids or alkalis to bring about this alteration.

[In 1919 work on the genus Oneilella was begun by the author and Mr. R. E. Turner. General agreement was reached as to the species represented in the material studied, and a table constructed before Mr. Turner's return to S. Africa. Subsequently all the additional material now dealt with was seen by Mr. Turner, and determined in collaboration.]

The genus Oneilella, Cam. 1904, created for the reception of Cryptus formosus, Brullé 1846, has up to the present remained monotypic. That it contained many more species was evident after an examination of the examples of this genus available in the British Museum collection and in various collections forwarded for identification to the Museum or received through the Imperial Bureau of Entomology. The material so gathered together (over 450 specimens) is, with one doubtful exception, African in source and dates from 1848 onwards. Its analysis has been a matter of some difficulty and has been undertaken chiefly because of the economic importance of some of the species. In the following pages an attempt has been made to summarise our present knowledge of the genus and its parasitism, and to describe such forms as appeared to be new.

Afroryzophilus djibai is a new genus and species of weevil, which attacks rice in Senegal. Its biology, pest potential and relationships with other Erirhininae are discussed.

Having taken part as a volunteer in the great yellow fever epidemic of 1905 in New Orleans, I was later in the same year sent by the Colonial Office to enquire into yellow fever in British Honduras and the adjacent Central American Republics.

The method of poisoning flies by the exposure of solutions of sodium arsenite and sugar is one that has been advocated by entomologists in Italy and in South Africa for some years, and yielded good results in Mesopotamia in 1916; for in hot climates, where flies come readily to sugar solutions, the use of an outdoor poison is specially valuable. But there are obvious disadvantages in using any arsenic solutions; for not only are they poisonous in themselves, but the disposal of residues is not easy, as the arsenic and sugar remain poisonous if thrown away, or if they dry on sand or soil. It would thus be useful to substitute for arsenic some compound less poisonous to man and less stable in a soluble form when thrown away.

A DDT sol, prepared in glass dishes in the manner described, has a reproducible zeta potential of −25 mv. Electrophoretic measurements showed that DDT conditioned in cardboard cartons has a zeta potential of zero.

The zeta potential of the suspension behaves in a predictable and measurable manner in the presence of mono-, di-, tri-, and tetravalent ions.

Spectrographic analyses showed that there are two identifiable sources of ions: (1) the DDT, and (2) the cardboard container. A third source of ions was indicated as being, singly or together, the distilled water and/or the DDT solvent.

Spectrographic data showed that ions were associated with the conditioned DDT.

In glass containers, a poor source of ions, kill of larvae of Anopheles quadrimaculatus Say was higher than in paper containers, a good source of ions. These data are correlated with the zeta potential and flocculation behaviour of DDT suspensions.

A chalcidoid wasp, Torymus apiomyiae sp. n., is described from material reared in southern Yugoslavia. The host is Apiomyia bergenstammi (Wachtl), a gall midge galling young fruit-bearing twigs of pear trees, which is locally a serious pest.

The following note records the Ceratopogoninae found in two collections of small insects made by Dr. J. F. Corson at Dar-es-Salaam, Tanganyika Territory, East Africa, 1st to 20th September 1925. All the insects were taken between 5.30 p.m. and 6.30 p.m. on the windows of either the Bacteriological Laboratory or of a bungalow. We have pleasure in dedicating to the collector the single new species found.

A small number of Haematopota from the Congo were recently sent for determination to the British Museum by M. E. Roubaud of the Pasteur Institute. Among these were specimens of an interesting new species of the H. pertinens group, and as M. Roubaud was kind enough to say that the type of this species might be deposited in the British Museum, I undertook to describe it, including at the same time, at Dr. G. A. K. Marshall's request, descriptions of a few of the numerous unrecorded African species of this genus in the collections of the British Museum and the Imperial Bureau of Entomology.

Whilst the status of Capnodis as a pest in Israel has been considerably reduced by the control measures that have been adopted, it was considered desirable to test the new synthetic contact insecticides, in particular DDT and BHC.

Techniques for the determination of the effect of insecticides on neonate larvae of Capnodis are described and the results discussed.

It is shown that BHC and DDT are ineffective as fumigants against the boring larvae.

Used as a contact insecticide against the larvae, a high degree of mortality is obtained with 5 per cent. BHC over a period of 50 days. DDT is far less effective. BHC, dieldrin and methoxychlor remained effective for over a year if left undisturbed in the ground.

Against adult Capnodis, BHC gave results comparable to those obtained with cryolite and retained its activity for at least twelve days after application.

Amongst a number of larvae collected in the Yokeskei River, about twelve miles from Johannesburg, on 31.v.1928, two were found which appeared to be new. These subsequently pupated and finally hatched, one on 15.vi.1928 and the other on 18.vi. 1928. The adults were seen to be Anopheles argenteolobatus, Gough. Repeated collecting after this has failed to reveal further specimens. Larvae of the following mosquitos were found in the same pool: Anopheles squamosus, A. cinereus, A. rufipes, Culex salisburiensis, and C. theileri.