In connection with the study of Anopheline pupae with Dr. P. A. Buxton, I extended my comparisons to the Culicine pupae accessible to us, in the first place to discover their differences from Anopheline pupae, and in the second to bring the Culicine pupae themselves into a system. As with the Anopheline pupae, I limited my comparisons to the trumpets and the chaetotaxy of the abdomen, especially of the last three abdominal segments.

Antennae ⅔, basal joint with distinct pecten; serrate and shortly ciliate in ♂. Labial Palpi long, recurved, both joints smoothly but somewhat thickly clothed, with furrow beneath; terminal joint distinctly shorter than median. Maxillary Palpi appressed to haustellum. Haustellum well-developed, scaled. Ocelli absent. Head and Thorax smoothly clothed with appressed scales. Forewings elongatelanceolate, apex blunt-pointed: neuration, 12 veins; 7–8 stalked, 7 to costa; rest separate, 2 remote from 3, 5 approximate to 4; 1 basally furcate. Hindwings 1+, trapezoidal, apex pointed, termen sinuate beneath: neuration, 8 veins; 6–7 very closely approximate toward base; 3–4 connate; 5 parallel to 4. Abdomen moderate. Legs: hind tibiae and the long basal joint of tarsi haired above, laterally compressed.

Observations were made at Dorimon in the extreme north-west of Ghana, during the hot months of March and April 1954, of the infectibility of Glossina palpalis (R.-D.) and G. tachinoides Westw. with Trypanosoma vivax.

Pupae were obtained from the Black Volta where shade temperatures ranged from 70 to 98°F. and the flies that emerged from them were kept singly in small glass tubes in the laboratory at a temperature of 85 to 95°F. and a relative humidity of 60 to 80 per cent. They were given several feeds on infected goats. The following percentage rates of infection were observed.

Labrum and (or) hypopharynx: General rate, 56·1; males of G. palpalis, 72·2, females, 34·6; males of G. tachinoides, 68·4, females, 56·8.

Labrum only and labrum & hypopharynx: General rate, 37·4; males of G. palpalis, 27·8, females, 15·4; males of G. tachinoides, 68·4, females, 40·9.

Early infection is the rule but late infections occurred. Some flies appear to be uninfectible. Thus, out of 107 flies, 47 remained uninfected in spite of having had on the average 10·6 infective meals per fly. A high percentage of flies lost their labrum infection.

The following percentage loss of labrum infection was recorded: General rate, 48.8; males of G. palpalis, 66·7, females, 62·5; males of G. tachinoides, nil, females, 43·8.

G. tachinoides appears to be more tenacious of infection than G. palpalis. Feeding infected flies on goats in the negative phase and (or) on spurwing goose (Plectropterus gambensis) did not appear to have any adverse effect on the colonies of trypanosomes in the labrum.

The apparatus previously used to demonstrate the repellent properties of DDT, fuel oil and methylated naphthalene auxiliary solvents towards certain Diptera was used in further studies of olfactory repellency in an attempt to narrow down the ingredients responsible for this effect, and consideration was given to the possibility of finding substitutes for them with less repellent or even attractive properties.

Light, medium and heavy fractions were obtained by fractional distillation of fuel oil and each of two methylated naphthalene auxiliary solvents. In all these spray components the repellent properties are inversely related to the boiling point, and appear to be non-specific both chemically and by insects. Tests with materials of low volatility, however, showed that the effect is not a simple broad relationship between volatility and repellency.

Butoxy-polypropylene glycol, widely used as a ‘repellent’ ingredient of livestock sprays, shows olfactory attractiveness to Musca domestica L. and Aëdes aegypti (L.). The odour of Drosophila melanogaster Mg. was shown to be attractive to the insect, regardless of sex.

It is concluded that there seems little hope of an economic non-repellent material.

It is suggested that the repellency of spray components might be counteracted by the addition of specific attractants, sex or other, to spray formulae. Alternatively, a useful space repellent spray, containing no toxicant, might be formulated from the lighter fractions of the solvent materials.

Sixteen varieties of Rubus, comprising four species, were tested with the Aphid, Amphorophora rubi (Kalt.), which is a vector of virus diseases of Rubus in Europe and N. America, to establish the range of resistance to the development of populations of the insect. The phenomenon of resistance was then further investigated from the aspect of fecundity, reproductive rate, length of life, growth rate and behaviour of the Aphid. In these latter investigations only four varieties of raspberry were employed. The varieties Malling Promise and Lloyd George showed no resistance. Malling Landmark proved to be highly resistant but showed a slight reduction in resistance in the autumn. Newburgh appeared to occupy an intermediate position between Malling Landmark and the other two varieties. There were indications, however, that under field conditions its degree of aphid resistance may be greater than was observed under experimental conditions. Resistance seems to involve a slowing down of the reproductive rate, a shortening of the length of life of adults and prevention of development of the nymphs. The practicability of using aphid-resistant varieties of raspberry to minimise virus spread is discussed.

Various species of Curculionidae are injurious to orchards in Ukraine, but Sciaphobus squalidus, Gyll. (fig. 1) is considered by fruit-growers to be the most harmful, as it attacks the buds of all fruit trees. Mr. Znamenskii was the first to make an adequate study of the life-history of this insect. The following notes give an account of my own observations and deal principally with methods of control.

In this paper four new species are described and two already known ones are discussed. The justification for bringing forward new species in a genus whose Old World members are in a state of great disorder lies in the fact that their hosts are known and are Lepidopterous pests of economic importance.

The types are in the British Museum.

Anagyrus beneficians, Compere, obtained in small numbers from shipments of other parasites from Uganda, proved to breed readily in the laboratory.

Numbers were reared, liberated and established on mealybug in coffee districts and native reserves in Kenya.

It is one of several parasites responsible for a marked reduction in the severity of the mealybug.

A new species in the genus Phycita, the larva of which is a pest of eggplant in Nigeria and Senegal, is described and named P. melongenae sp.n. Notes on its biology and illustrations of the adult insect and genitalia of both sexes are given

Head and thorax dark; abdomen pale, apparently pale green, with dark lateral spots. Antennae, cauda and cornicles dark. Legs with mid and hind femora dark, front pair paler; apices of tibiae and the tarsi dark. Antennae shorter than body, rather thick; basal segment larger and paler than second; third much longer than fourth and about as long as the sixth, with 18–20 small round pale sensoria over its whole length; fourth segment very slightly longer than fifth, with 5–8 sensoria; fifth with 4–7 sensoria of unequal size, exclusive of the usual subapical one; sixth with the rather thick basal area less than one-third the length of flagellum, in some however almost half its length; all the segments from the third imbricated. Eyes large. Proboscis reaching to the third coxae. A large palebladder-like papilla on each side of pronotum and five pairs of pale rounded papillae on sides of abdomen. Cornicles about as long and as thick as third antennal segment, cylindrical, markedly imbricated, not reaching to the level of the cauda. Cauda bluntly pointed, about half the length of the cornicles, spinose; with numerous fine hairs, curved apically. Anal plate spinose, with fine pale hairs. Tibiae with numerous fine, pale, short hairs. Wings with normal venation; veins and stigma brown, the veins very faintly and narrowly clouded on each side. Length, 2–2.2 mm.

♀.—Length (four specimens) 13 to 16 mm.; width of head 4·4 to 5·5 mm.; width of front at vertex 0·5 mm. to just under 1 mm.; length of wing 10 to 13 mm.

Lycidocoris, Reut. & Popp., Trans. Ent. Soc. Lond., 1911, p. 409; Popp., Acta Soc. Scient. Fenn., xli, p. 182 (1912).

Winged and wingless individuals of Myzus persicae (Sulz.), when offered a choice between unsprayed cauliflower seedlings and seedlings sprayed with a 0·1 per cent. aqueous solution of Lissapol N (a non-ionic wetting agent), preferred Lissapol-treated plants. This effect was statistically significant.

Further experiments showed that Aphids similarly preferred treated turnip seedlings to untreated seedlings. The preference for sprayed cauliflower seedlings was also shown when an anionic, a cationic and a mixed wetting agent were used.

Like Mauritius, many other cane-growing countries in the world are suffering severely from the ravages of Lamellicorn beetle grubs. In some of these countries, such as Australia, India, South America and the West Indian Islands, these insects are indigenous, whilst in others, such as Hawaii and Mauritius, some of them have been accidentally introduced.

Through intensive cultivation of sugar-cane, which in some places is the staple industry, these so-called white grubs have found an abundance of food and an adequate environment, so that they have become, even in their country of origin, a major pest of sugar-cane ; whilst in places where they have been introduced, the damage done, in some cases, is a serious menace to the sugar industry.

Heavy annual losses are being sustained in the Philippines, Queensland and Porto Rico ; at present the damage in Porto Rico is estimated to be 3 million dollars yearly.

In order to cope with such a state of affairs, all possible effort is nowadays being made in most of these countries to try to control the pests by rational and scientific methods. Though many important points have been solved by research workers engaged thereon, there still remain many unknown factors upon which enlightenment is required.

♀.—Length (3 specimens) 15·6 to 16·5 mm.; width of head 6·25 to 6·5 mm.; width of front at vertex 2·5 mm.; length of wing 14·75 to 15 mm.

In the Bulletin of Entomological Research, Vol. I. pp. 60–61, I gave an account of the ravages of a cocoa bark-sapper (Sahlbergella theobroma, Dist.), which was found destroying cocoa trees upon plantations in some parts of the Gold Coast and Ashanti, where, by reason of its wide distribution in 1909, it promised to affect the industry seriously.

Broad-spectrum insecticides are the main control measure of the invasive and economically damaging soybean aphid (Aphis glycines) in North America, although biological control by resident natural enemies can also greatly diminish population levels. One such natural enemy is the accidentally introduced Eurasian parasitoid Aphelinus certus (Hymenoptera: Aphelinidae), though its impact appears to be limited by low rates of parasitism early in the growing season. We tested the hypothesis that A. certus might experience high overwintering mortality. In the laboratory, we used thermocouple thermometry to measure the supercooling points of diapausing parasitoids and assessed parasitoid survival after exposure to ecologically relevant durations of low temperature. We found A. certus to be freeze-intolerant with a median supercooling point of −28°C. When exposed to temperatures of 0°C for up to 7 months, adults emerged only after exposures of at least 60 days and survival decreased with durations beyond 150 days. We also conducted in-field studies at sites from northern Minnesota to southern Iowa to determine if diapausing A. certus could overwinter above and below the snowpack. Survival was negatively correlated with increasing latitude and was greater for parasitoids placed on the ground than 1 meter off the ground, likely due to the warmer and stabler temperatures of the subnivean microclimate. Our results suggest that A. certus is capable of overwintering in the region inhabited by soybean aphid but may experience substantial mortality even under ideal conditions. Climate change is predicted to bring warmer, drier winters to the North American Midwest, with decreased depth and duration of snow cover, which may further reduce overwintering survival.

Termites are a significant pest of buildings, agriculture, and trees, and are mainly controlled by baiting. However, baiting systems are available for only lower termites (Rhinotermitidae) not for higher termites (Termitidae). Termite foraging behavior associated with baiting systems varies among species and families, and plays a significant role in baiting success. Here, foraging behavior of Odontotermes obesus (Blattodea: Termitidae: Macrotermitinae), a fungus-growing higher termite, was investigated relative to three bait-station sizes (small, medium, and large) containing different quantities of food. Significantly more workers recruited to large stations (470/station) compared to medium (246/station) and small (124/station) stations. Abundance of O. obesus in large and medium stations significantly positively correlated with relative humidity whereas negative but non-significant correlations were observed with temperature in large and medium stations. Total and continuous contacts with the stations increased with time and were greater in large stations. Station abandonment due to disturbance was significantly less in large stations (3%) followed by medium (9%) and small stations (20%). Our results suggest that large stations (≈8 litres volume) work best for population management of O. obesus and other related fungus-growing higher termites.

Superparasitism is an adaptive strategy in solitary parasitoids, yet insufficient evidence confirms this in gregarious ones. We here ask whether the gregarious parasitoid Oomyzus sokolowskii is able to discriminate in attack and progeny allocation between parasitized and unparasitized Plutella xylostella larvae, and how the parasitoid allocates brood size and sex to superparasitized hosts due to some circumstances. We found that female parasitoids preferred unparasitized to parasitized host larvae, and allocated a smaller brood with more males in the later than in the former host. Brood size and sex ratio decreased from superparasitized hosts with a 48 h interval since a previous attack compared with one without an interval; they also declined from the host superparasitized by the parasitoid with oviposition experience compared with one without it. Brood size and sex ratio did not differ between the host superparasitized by the same parasitoid as in the first attack and that by a different one. Our findings suggest that O. sokolowskii females may adjust their oviposition decisions on progeny allocation in response to parasitized P. xylostella larvae to maximize their fitness gains from superparasitism.

Zinc finger protein (Zelda) of Tribolium castaneum (TcZelda) has been showed to play pivotal roles in embryonic development and metamorphosis. However, the regulatory mechanism of TcZelda associated with these physiology processes is unclear. Herein, the developmental expression profile showed that Zelda of T. castaneum was highly expressed in early eggs. Tissue expression profiling revealed that TcZelda was mainly expressed in the larval head and adult ovary of late adults and late larvae. TcZelda knockdown led to a 95% mortality rate in adults. These results suggested that TcZelda is related to the activation of the zygote genome in early embryonic development. Furthermore, 592 differentially expressed genes were identified from the dsZelda treated group. Compared with the control group, altered disjunction (ALD) and AGAP005368-PA (GAP) in the dsZelda group were significantly down-regulated, while TGF-beta, propeptide (TGF) was significantly up-regulated, suggesting that TcZelda may be involved in insect embryonic development. In addition, the expression of Ubx ultrabithorax (UBX), Cx cephalothorax (CX), En engrailed (EN), and two Endocuticle structural glycoprotein sgabd (ABD) genes were significantly down-regulated, suggesting that they may cooperate with TcZelda to regulate the development of insect wings. Additionally, Elongation (ELO), fatty acid synthase (FAS), and fatty acyl-CoA desaturase (FAD) expression was inhibited in dsZelda insects, which could disturb the lipase signaling pathways, thus, disrupting the insect reproductive system and pheromone synthesis. These results may help reveal the function of TcZelda in insects and the role of certain genes in the gene regulatory network and provide new ideas for the prevention and control of T. castaneum.