There is a growing body of evidence to suggest that low density populations of Spodoptera exempta (Walker) in the solitary-phase can persist during the dry season in certain localities in eastern Africa. Moths were caught in simple pheromone traps for several months after the estimated dates of emergence of larval outbreaks in central Tanzania in 1980 and from 1982 to 1984. This provided evidence for the occurrence of a shifting population between the Uluguru Mountains and the swampy coastal areas, in east-central Tanzania, for a large part of the year. Central Tanzania is an important area for the development of the first outbreaks of the season in eastern Africa and for any control strategy. It has been suggested that S. exempta fits the criteria for an r-selected species. However, the low migratory capacity of low-density populations indicates rather that the species spreads out its risks in space and time. A theoretical genetic mechanism controlling the distance flown by moths may enable the species to exhibit both migratory and non-migratory strategies. Thus both ephemeral and continously favourable habitats may be exploited.

The description of the ten Chamaesphecia species associated with Euphorbia in eastern and south-eastern Europe is based on external adult morphology, male and female genitalia, and the structure of the egg chorion. These species can be divided into two groups according to the shape of the setae of the dorso-basal part of the valvae in the male genitalia. Most Chamaesphecia species are associated with one species of host-plant and all are closely tied to one habitat type. The host-plant and the structure of the egg chorion are fundamental characteristics for the determination of a few species, and very helpful for the others. All species bore into the main root of their host-plant and overwinter as larvae. With the exception of two species which have an annual or biennial life cycle, all species are univoltine. The larvae of three of the eight Chamaesphecia spp. investigated feed and develop in the roots of North American leafy spurge, Euphorbia esula sensu lato. Of these, the best candidate for the biological control of leafy spurge is C. crassicornis, because the larvae have a similar survival rate on the target weed and the European host-plant, E. virgata.

Grain losses per unit area in oats following shoot attack by frit fly (Oscinella frit (L.)) were assessed in plots at Rothamsted. Individual plants were marked, and two categories of attacked plants (tillers and both main shoot plus tillers attacked) were distinguished because losses in the former were low or negligible compared with those in the latter. There was no evidence of compensatory growth for lost or damaged plants, so that losses could be assessed by comparing actual yield with yield expected had no plants been attacked. The percentage loss, weighted according to incidence and effect of attack in the two categories, was calculated from hand-harvested samples. The loss per unit area was then estimated from the actual yield obtained by combineharvesting. Estimates of actual yield were affected by the method of harvesting, so that estimates of loss were not precise.

Visual and olfactory responses of Glossina fuscipes fuscipes Newstead to the monitor lizard, Varanus niloticus niloticus Laurenti were studied using various catching devices near Lake Victoria, Kenya. Electric nets baited with visible lizards caught more males (×2.1) and significantly more females (×2.0) than unbaited nets. Lizards concealed in electrified black PVC pipe models, simulating the shape and size of a monitor lizard, increased significantly the catches of tsetse by 2.1 times. Fresh lizard urine dispensed at an evaporation rate of 500 to 1000 mg/h also increased significantly the catches of flies at biconical traps, electrified models and electric nets. Identification of chemical constituents of the odour could improve monitoring and control strategies for G. f. fuscipes, and possibly for other palpalis tsetse species.

When I assumed duty in the Nile Province of the Uganda Protectorate, it was known to me that Dr. Shircore had taken a tsetse-fly near Nimule, which he considered to be nearly allied to, but distinct from, G. palpalis. I had been asked to take an early opportunity of examining the haunt of these insects and capturing further specimens. On several occasions I therefore repaired to the site of Dr. Shircore's find, and along some two miles of the bank succeeded in taking a large number of Glossina. These did not appear to differ in any noticeable degree from those one had seen on Lake Victoria, or on the smaller rivers of this Province, and as Dr. Shircore had reported that he had frequently seen the fly in question with the larger palpalis, especially near Nimule, I came to the conclusion that I had been very unfortunate in not taking a single specimen.

1. From a block of country of four square miles, infested by Glossina swynner-toni and a few G. pallidipes, grass-fires have been excluded for three years in succession. The tsetse-population has decreased in that time by nearly nine-tenths (from 9.4 to 1.0 flies per 1,000 yards of transect). In a block of two square miles it has decreased in two years without burning to the same average of one fly per thousand yards of transect from a high previous figure unmeasured. Two “barrier” strips following roads that previously were highly infested have also been unburned for three and four years respectively and have become similarly inhospitable to the flies.

2. In a control block of only 1¾ square miles, the grass has been burned in the ordinary native fashion annually during the same period. The average fly-catch per thousand yards of transect has increased since this was done from 4.2 to 13.1.

3. In each of these blocks game is about as plentiful as it was at the first. The 4-square-mile block shows a slight gain.

4. In the four experimental blocks and strips, but not in the controls, extensive thicket is growing up everywhere in the grass as a result of the exclusion of the fires. Thus the previous marked difference, both spatial and seasonal, between the respective densities of the different vegetational communities is commencing to disappear. Much grass-country remains but its average condition is one of long grass rising from a mulch, thick or thin and sometimes absent, of the previous year's grass that keeps the soil damp after rain—the more so since run-off is checked. Longer and denser grass is encroaching into the previously very open concentration sites of G. swynnertoni, which are also being invaded by thicket.

5. The contrasts between burned and unburned country are especially strong in the short wet season. At this time in burned country the flies have just gone through a period of intense desiccation, short hunger cycle and hardship, and the population is at its annual minimum. The ground, however, is very open and visibility of the other sex and of food animals and breeding-places is unimpeded. Conditions are suddenly made ideal by the advent of the rains. Humidity is added to temperature; the hunger cycle is lengthened; the openness and insolation of the ground now probably play a further beneficent part by preventing an excess of humidity. The flies are active, they breed freely, the shade conditions enable them to spread, and the density curve soars upward.

On the unburned ground the water-content of the soil is increased in the early rains, dampness is retained between showers, the temperature is lowered, evaporation is reduced, and light intensity in the grass becomes less (Scott, 1934). The activity and breeding of the flies is quite likely affected. The striking increase in the population that characterised unburned country in the early rams and short dry season is absent, and the density, having failed to rise at this time, continues low or falls further.

6. In two cases (G. morsitans, Nash 1933, at Kandaga; G. swynnertoni in Block 11 at Shinyanga) the second annual impetus to breeding, associated normally with the advent of the long dry season, duly produced its usual effect on the tsetse-populations of country that was in its first year of no burning. In the case of the block that has been unburned for three years this effect has been slight.

7. That the conditions, though deteriorating, are as yet not lethal through hunger, due to poor visibility or otherwise, is suggested by the fact that the very small fly populations referred to maintain a nearly stationary balance in at least the larger experimental block and do not show special hunger or other sign of distress. It is possible that most of the diminution hitherto has been caused merely by emigration to better conditions, for the blocks are not yet fully isolated. On the other hand, were the main effect on the breeding, distress would not be detected and the result might take place independently of any emigration. Reduced visibility of food animals may become operative later.

8. It is suggested by the results so far on the tsetse and by the present appearance of the country in these four experiments that with the further advance of the vegetational succession towards its natural climax the remaining fly population will probably dwindle further and disappear—at least if the areas are isolated; the growing homogeneity in the density of the whole vegetation will reach a point at which it is unlikely to satisfy the daily and seasonal needs of an insect which for food, breeding and regulation of moisture and temperature, has a separate and vital use for each of the three densities furnished by thicket, savannah wooding and nearly open hard-pan and vlei.

9. The concentration sites of G. swynnertoni combine in a small space the types of vegetation the flies need, both the denser and the more open. They are important at all times but especially as refuges from unfavourable conditions elsewhere and as meeting-grounds of the sexes when the population is reduced. They are operative all the year round, and an effective change in these refuges alone in either the wet season or dry should be a shrewd blow at the fly. In experiments elsewhere in Shinyanga the clearing of the thickets at these places has quickly brought down the fly-population through its dry-season effect. In Blocks 4A and 10A the cessation of grass-burning is apparently already affecting these sites by hemming them in with areas presenting unfavourable conditions—probably mainly through excessive shade and over-humidity in the rains. The cessation of burning might even suffice if confined to these concentration sites and their neighbourhood.

10. As regards the probable effect of not burning the grass on other species of tsetse, it is considered that the method may prove useful against G. morsitans under moderately extensive vegetational conditions, though it may in this case take much longer and may not apply to large areas. Berlinia-Brachystegia wooding went to thicket in the writer's early experiments in a specially high rainfall area in Rhodesia, and (under lower rainfall) the exclusion of fire for five years at Itundwe (Central Province, Tanganyika) has produced strong densification in the Berlinia. In the Kikore plots (5 years protected) savannah type seedlings are being suppressed by the new conditions, but the flourishing state of the few shade-tolerating thicket plants suggests that all that is wanted is the introduction of a suitable seed-supply. This will be necessary in any case in all places without natural regeneration.

11. In an observation by Nash (Kandaga, Central Province) G. morsitans reacted initially in much the same way as G. swynnertoni, but the experiment was interrupted. In Itundwe G. morsitans and its pupae are much less numerous in the unburned Berlinia than in the burned.

12. The reaction of G. pallidipes, as distinguished from that of its habitat, is uncertain but so far has been promising under Shinyanga conditions; but the new conditions at Itundwe look as though they might favour this fly. G. brevipalpis is definitely likely to be favoured by the effect of not burning the grass.

13. The increase in humidity and lowering of the temperature produced by not burning the grass may be expected to be specially effective towards the wet side of a tsetse-fly's range. Towards the dry side it might even at first assist the fly.

14. Experiments to test the possibility of success against morsitans are being taken in hand, as are experiments on larger pieces of country infested by swynnertoni and pallidipes.

15. The control of grass-fires offers difficulties, but our experience over a wide area and many years shows that with determination and organisation it is quite possible, though an occasional minor set-back must be expected. The advantages of this measure from other points of view than that of tsetse extirpation, and the means of restoring the pasture, are referred to on p. 425.

A new easily-produced cheap compound for use as a bait matrix is described. The light-weight matrix of polyurethane is prepared from dense precursors into which suitable attractants and toxicants can be incorporated for the pest species in question. It has a high bait effectiveness/weight ratio, and so is very suitable for aerial application as large economically viable payloads can be achieved. When tested both in the laboratory and in the field on a small scale against the leaf-cutting ant Acromyrmex octospinosus (Reich), the bait was highly acceptable to the ants. Some formulations, especially those coated with mirex gave excellent control of ants in the field in Trinidad, killing all occupants of nests within four days of baiting. The bait exhibited good weathering properties, was resistant to fungus attack, and allowed the slow release of pheromones. It was much cheaper than the citrus pulp baits normally used in Trinidad.

Among the insects which do serious damage to grasses grown for seed, the larvae of gall midges (Cecidomyidae) are of great importance. Very little is known about their bionomics, except in the case of the Sorghum midge (Contarinia sorghicola), and the Meadow Foxtail midges (Dasyneura alopecuri, Contarinia merceri, and Stenodiplosis geniculati). In view of this and the fact that several grasses are grown for seed with advantage in Great Britain, it has been thought advisable to collect together all the available information.

Eupelminus tarsatus, Waterst. (1916).

Eupelminus tarsatus, Waterston, Bull. Ent. Res., vi, Feb. 1916, p. 389, figs. 7 and 8 ; Lamborn, ibid., vii, May 1916, p. 34.

A series of both sexes of this parasite of Glossina morsitans enables me to describe the male for the first time and the female more fully. One of the striking features about this species, apart from its remarkable sexual dimorphism, is the great range in size which it exhibits. The females run from 3½ mm. to 5 mm. and the males from 1½ mm. to 2¼ mm., with a range in the alar expanse of 2¼ mm. to 3¾ mm. The larger female examples are invariably darker and more metallic in coloration. Dr. Lamborn is certainly right in correlating the smaller size of some of the parasites with a reduced food supply (l.c. p. 35). I cannot yet agree, however, that the parasitic status of E. tarsatus is definitely fixed by our present knowledge of its habits. Plainly the proportion of Mutilla-parasitised puparia supplied to the Eupelminus females was larger than could have occurred under natural conditions. Again, the factors, whatever they are, inducing Mutilla to oviposit in a particular puparium may be equally decisive for the female Eupelminus. If, for example, in two cases three Eupelminus punctures all close together could be seen with a high-power lens one might suggest that some structural peculiarity invited the attack. Nor, incidentally, is it legitimate to infer that because a puparium observed to be stung produced no Eupelminus the attack had failed. The presumption is that the attack had not been delivered, stinging and ovipositing being, in many cases, two separate processes. Many Chalcids plunge the ovipositor into ova, puparia, etc., and then, applying the mouth to the wound, suck up the contents which have been expelled. In other cases the first stinging observed is merely the narcotising and rendering antiseptic of the host, which precedes the real introduction of the ova. The parasitic status of Eupelminus can, in fact, be settled only by examination of puparia, collected under natural conditions, from which the Chalcids have been noted to emerge.

The most favourable areas for the cultivation of grape-vines in Ukraine are the sands of the lower reaches of the Dnieper in the district of Kherson, the shore of the Black Sea, the Kherson-Odessa districts, and along the Sea of Asov, chiefly in the district of Mariupol. Moreover, as is well known, vines do not suffer from Phylloxera when grown on pure sand. For these reasons, numerous State Departments, and also many private individuals, have spent a great deal of money in utilising this enormous extent of shifting sands for growing grapes.

The unexpected appearance of the larvae of various Scarabaeid beetles, especially Polyphylla fullo, L. (fig. 1), has been a great obstacle to the successful exploitation of these barren spaces. The larvae in the soil generally average about 10–12 to the square metre, and they often completely destroy the newly planted vines in one summer. Many enterprising persons have thus been ruined in their endeavours to form vineyards on the sands. It was stated officially in pre-war times that these pioneers had spent over £2,000,000 sterling without any result.

In April 1947, the laboratory stock of Glossina palpalis, R.-D., puparia collected from the Kaduna area suddenly became heavily infested with the pupal parasite, Syntomosphyrum glossinae, Wtstn. Presumably an infected pupa had been brought in from the bush and a few parasites had emerged undetected; it was not until the emergence of their offspring that the mass-infestation was revealed.

Studies were made of populations of adult Rhyssa persuasoria (L.) from various geographical regions. Morphometric analyses were based on the relative size of 32 maculae on various sclerites and the colour of the coxae and legs. Size was determined by measuring the wing length and thorax length. Various statistical procedures were applied to these data and also the ratios of wing length: maculation, and thorax length: maculation in an attempt to distinguish races of R. persuasoria from different localities. Regression analysis, analysis of variance and classification procedures separated some populations from others, the results of the different analyses being in broad agreement with each other. Within each population, maculation was typically linear, smaller specimens having relatively small maculae. Some sexually dimorphic differences were also demonstrated. There were two major geographical groupings: S.W. European and North African (W. France, Spain, Portugal and Morocco) and the remainder. There were some geographical differences within the remaining populations although all had links with one or more adjacent populations. The degree of maculation was shown to be related to the colour and texture of host-tree species, populations with low maculation scores being associated with tree species having dark, fissured bark and vice versa. It is suggested that degree of maculation is an expression of cryptic colouration, providing camouflage from predators. Determinations of heat-coma temperature for male R. persuasoria from climatically different areas showed that the response to high temperature differed between populations and was correlated with the temperature of the locality of origin. These differences between strains were apparent after several months of identical conditioning and are probably genetically based.

The present notes are a short account of work of a preliminary nature on the Coast of Kenya Colony, mostly between August 1920 and February 1921, at the end of a tour of service, and may serve to indicate some of the chief points calling for investigation. They are concerned with the life-history of the insect and with some field observations. The life-history work was carried out in tents shaded by a large mango tree, on land kindly lent by Sheik Ali bin Salim, on the north side of Mombasa Island. The field work was done on the island and on the neighbouring mainland. For records of the numbers of beetles captured on European plantations I am indebted to three gentlemen owning or managing them.

Roubaud has recently recorded (cf. Sleeping Sickn. Bull., I l l, p. 419) that in West Africa G. morsitans is intolerant of high temperatures, as he has found that specimens exposed to 40° C. (104° F.) died within an hour. This species is however adapted to withstand such a temperature in the Luangwa Valley; for during the hot months of October and November the shade thermometer frequently registers from 106° to 108° F., seemingly without any ill results to the tsetses.

The presence of the yellow-necked drywood termite, Kalotermes flavicollis Fabr., has been reported along most of the Mediterranean coasts of Europe, Africa and Asia. While morphological and genetic data exist on European K. flavicollis populations from western and central Mediterranean regions, data on eastern Mediterranean Kalotermes are scarce, and no genetic data exist to date. In this study, we analyzed 17 Kalotermes sp. colonies from 11 localities in the Levant (Cyprus, Lebanon, and Israel), in order to characterize genetically (mitochondrial DNA: COII, 16S, and control region) these populations. We found that samples from the Levant are genetically different from K. flavicollis, with distance values falling in the range of interspecific distances. In the phylogeny of European Kalotermes populations, samples from the Levant form a clade of their own, sister to a clade including K. flavicollis and Kalotermes italicus. Inside the eastern Mediterranean clade, all the samples from Cyprus are included in a well-supported subclade, suggesting that the colonization of the island might have occurred in a single event. These findings show that the populations we examined do not belong to the species K. flavicollis, but to a new species peculiar to the Levant, that we describe as Kalotermes phoeniciae sp. nov. It is possible that previous reports of K. flavicollis in this region can be attributed to K. phoeniciae.

The performance (development and reproduction) of generalist predators can vary greatly among the prey species that they use, and these differences can influence the ability of predatory insects to suppress pest populations. The aim of this study was to compare the performance of larvae of the green lacewing Chrysoperla rufilabris (Burmeister, 1839) by offering 16 species of aphids and by assessing the effects of each species on the survival, larval development time, prey consumption, pupal mass and egg load of adult Chr. rufilabris females taking aphid phylogeny into account. Chrysoperla rufilabris larvae preyed on individuals from all 16 aphid species, but complete development, adult emergence and egg load production were achieved only in seven species. As a general pattern, the best levels of performance were achieved for an aphid clade that includes the soybean aphid, Aphis glycines (Matsumara, 1917), and for a milkweed-feeding species, Myzocallis asclepiadis (Monell, 1879). We found significant phylogenetic clustering for most of the performance traits indicating the aspects of specialization in the diet breadth of Chr. rufilabris despite the fact that this species is considered a generalist aphid predator. These findings can help us to understand the interactions of this species in agroecological food webs, where it is commonly found, and provide insights into why natural, conservation biological control or augmentative releases may succeed or fail.

Phenacoccus avenae Borchsenius, a mealybug described originally from beneath the leaf sheaths of a grass in Armenia, USSR, has been intercepted at quarantine in the Netherlands. USA and England on bulbs, corms and rhizomes of ornamental plants from Turkey. The mealybug, however, has never been recorded from Turkey although it probably exists there on monocotyledons. It is redescribed and illustrated here to facilitate identification at quarantine stations, and a list is given of its host-plants in the families Gramineae, Amaryllidaceae, Iridaceae and Liliaceae.

Anastrepha fraterculus (Diptera: Tephritidae) is a major barrier to fruit production and exportation. In Brazil, the native parasitoid Aganaspis pelleranoi (Hymenoptera: Figitidae) and the exotic parasitoid Diachasmimorpha longicaudata (Hymenoptera, Braconidae) stand out as biological control agents. Knowledge of the factors that affect interactions among parasitoids, A. fraterculus, and host fruits may enhance the use of these agents in biological control programmes. This study evaluated the chemotaxis and parasitism of A. pelleranoi and D. longicaudata females reared on A. fraterculus larvae and kept on an artificial diet, red guava (Psidium guajava) or apple (Malus domestica). Females of both parasitoid species that emerged from larvae raised on artificial diet, guava or apple, were tested to Y olfactometer choice tests. In the parasitism tests, both parasitoid species were made to choose between A. fraterculus larvae brushed with water, apple pulp or guava pulp. D. longicaudata females from artificial diet (control) did not distinguish between fruit odours; however, females of D. longicaudata from larvae kept in apple or guava directed to the odours of their original fruit. The greatest parasitism for D. longicaudata occurred in the units that contained the pulp in which the larvae grew. A. pelleranoi from artificial diet preferred guava odours, including the females kept in apple. Similar results were observed in the parasitism bioassays. Our results found that A. fraterculus larval feeding influenced search behaviour and parasitism of D. longicaudata, whereas A. pelleranoi rearing experience did not affect its host choices.

Collections of Cactophagus spinolae (Gylh.) were made in Mexico in 1946, 1947, and 1948 to supplement the biological control of prickly pear (Opuntia spp.) in South Africa. During these three years, 862, 1,396, and 15,584 adults, respectively, were dispatched to South Africa. The weevils were sent by air express in specially designed containers, and arrived in excellent condition.

This paper includes information on the distribution, life history and food preferences of C. spinolae. The need is stressed for anticipating the effects of transit conditions upon living insect material transported by aircraft.

A general survey of coconut plantations in Guyana in 1976 indicated that in the total area of about 18 700 ha, 1000 of the 3000 ha of coconut palms on the east coast of Demerara were infested by Azteca sp. Detailed crop loss assessments on four plantations in 1970–72 indicate that the overall loss of crop to this pest in Guyana in 1976 was about 3·7 million coconuts, valued at G$372 000. Damage is partly due to mealybug, Nipaecoccus nipae (Mask.), and scale insect, Aspidiotus destructor Sign., colonies maintained by the ants and may also be partly attributed to interference with pollinating insects. Chemical control with aldrin and dieldrin sprays applied to tree trunks to create insecticide barriers and applied to whole trees with a power-sprayer and extension lance did not give adequate long-term control. Baits based on minced bovine intestine with 2% v/w ethyl alcohol were therefore assessed in field trials. Aldrin at 0·3–2·4% a.i., nonachlor at 0·3–2·0% and mirex at 0·05–0·6% were tested. Bait containing 0·1% mirex gave best results with complete kill of ants' nests 60 days after application at about 5 kg bait/ha. Mealybug and scale infestations were also eliminated by this treatment with subsequent reductions of leaf-yellowing and increases of leaf number 100 days after treatment. Up to September 1976, 0·15% mirex bait had been used to control Azteca sp. on 200 ha of coconut palms in Guyana.