Research Paper
Field infestation of cowpea (Vigna unguiculata) pods by beetles of the families Bruchidae and Curculionidae in Northern Nigeria
- P. F. Prevett
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 635-645
-
- Article
- Export citation
-
An account is given of a study of infestation of cowpea pods in the field in Northern Nigeria by the weevil, Piezotrachelus varius (Wagn.), and the Bruchids, Bruchidius atrolineatus (Pic) and Callosobruchus maculatus (F.). Oviposition by Bruchids did not commence until the pods were fully formed and light green in colour, whilst infestation by P. varius originated in the young pods. Observations indicated that a high level of parasitism of Bruchid eggs occurred, but that the majority of Hymenopterous parasites emerging from within the pods were related to P. varius.
When pods were harvested at regular intervals, large numbers of P. varius emerged from the early harvests only. B. atrolineatus was the predominant Bruchid species emerging, particularly from early harvests. In the case of a single final harvest of pods, large numbers of P. varius, and a higher level of infestation by B. atrolineatus than in pods collected at regular intervals, were recorded.
Shelling of four batches of pods indicated a mean of 11 per cent, of seeds attacked by Bruchids in the case of single final harvests, and a mean of only 3·5 per cent, in the case of regular harvests as pods became dry. It is concluded that a considerable improvement in quality would result from an adoption of the latter method by farmers, provided that some method of control in respect of the harvested pods were introduced.
From the observations made it is concluded that P. varius is a true field pest, B. atrolineatus primarily a field pest able to continue infestation in store to a very limited extent, and C. maculatus primarily a store pest able to commence its infestation in pods in the field and to build up in numbers rapidly during the immediate post-harvest storage period.
The normal manner of cultivation precludes the use of field methods of control at oviposition peaks but observations suggest that elimination of secondary hosts of P. varius and B. atrolineatus might be worthwhile. A reduction in oviposition by C. maculatus by treatment of stored cowpeas in growing areas, and treatment of pods during the immediate post-harvest storage period, should considerably reduce the level of infestation by this species.
Seasonal variation in size and colour, and daily changes in the distribution of Glossina pallidipes Aust. in the South Busoga forest, Uganda
- J. P. Glasgow
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 647-666
-
- Article
- Export citation
-
The daily distribution of G. pallidipes Aust. was studied on a spiral fly-round covering 180 acres in the South Busoga forest of Uganda in 1954–55. G. brevipalpis Newst. also occurred in the forest, and, rarely, G. palpalis fuscipes Newst. Seasonal changes occur in the size of G. pallidipes, but are less marked than those reported from other places. The size of G. brevipalpis also varies with season. Seasonal colour changes in G. pallidipes indicate that in the driest season about half the puparia experience relative humidity as low as 70 per cent.
Catching was done at 349 (later increased to 373) points on the spiral. Mathematically, the catches on a single day, or the sum of many days, conformed to a negative binomial distribution. Although this indicates an uneven distribution, it is pointed out that one negative binomial is compatible with many different distributions on the ground. For this reason the negative binomial is not a satisfactory summary of data which at present can only be shown satisfactorily on a map.
Comparison of maps of catches on successive days shows a confusing pattern of vague and ill-defined patches of flies moving about in an unpredictable fashion. A definitive pattern appears only when many days' catches are summed. Such apparently random movement explains the high variance between days' catches previously reported. Sometimes very large numbers of G. pallidipes were found in a small area. As an index of such concentrations, the smallest area which could contain half the day's total catch was determined. Arbitrarily, when half the day's total catch was found in 5 per cent, or less of the total area, a concentration was said to exist. During 16 months' work, concentrations of tsetse, as defined by this criterion, were observed 16 times. Sometimes, but not always, the concentrations followed immediately after the passage of a herd of elephants or buffaloes, and it is concluded that these animals probably caused these concentrations, although the manner in which they may do so remains obscure.
The histochemistry of the cholinesterases in the central nervous system of susceptible and resistant strains of the house-fly, Musca domestica L., in relation to diazinon poisoning
- Frances M. Molloy
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 667-681
-
- Article
- Export citation
-
The distribution of cholinesterases hydrolysing acetyl- and butyrylthiocholine in the brain and thoracic ganglion of Musca domestica L. was examined histochemically in untreated flies, and in flies poisoned with diazinon (O,O-diethyl 0–2–isopropyl–4–methyl–6–pyrimidinyl phosphorothioate) of both susceptible and resistant strains.
The inhibition of cholinesterase after poisoning was, to a greater or lesser extent, confined to the peripheral region of the ganglia, and to other specific areas such as the suboesophageal ganglion and lamina ganglionaris. The extent of inhibition increased with increasing doses of poison, and increasing time after treatment. The degree of inhibition could be broadly correlated with the condition of the fly; badly affected or moribund flies having less active cholinesterase than living and unaffected flies. Together with these areas of more or less complete inhibition were other areas, especially in the neuropile or synaptic regions, in which there remained large amounts of active enzyme. Active enzyme was still present in these areas 24 hours after apparent death of the fly. Total inhibition of cholinesterase throughout the central nervous system was rarely seen, even after very high doses of diazinon causing over 99 per cent. kill.
Inhibition did not occur in the ganglia of living flies of a diazinon-resistant strain after a dose which caused inhibition and death in the normal susceptible strain. With 25 times this dose, causing approximately 99 per cent, kill in the resistant flies, cholinesterase was inhibited in them also, although to a somewhat lesser extent than in the susceptible flies given a comparable lethal dose.
The data provided strong evidence that if death is caused by inhibition of cholinesterase of the nervous system it is due to local inhibition and not to generalised inhibition.
Further Field experiments on the control of wheat bulb fly, Leptohylemyia coarctata (Fall.)
- F. E. Maskell, R. Gair
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 683-693
-
- Article
- Export citation
-
Field trials were conducted in certain eastern counties of England in the years 1957–1959 to assess chemical control methods applied at sowing time against wheat bulb fly, Leptohylemyia coarctata (Fall.). Combine-drilled treatments, using fillers of aluminium silicate, brick dust, granular clay, superphosphate or compound fertiliser, included aldrin at rates from 0·3 to 5·5 lb., dieldrin at 2 and 4 lb., and heptachlor at 2 lb. active ingredient per acre, respectively. Seed-dressing treatments applied with organo-mercury fungicide included 40 and 60 per cent. dieldrin and heptachlor, 40 per cent. aldrin, 60 per cent. Thiodan, 40 per cent. γ BHC with and without organo-mercury, all applied at 2 oz. per bushel of seed; 60 per cent. dieldrin, heptachlor and Thiodan were also tested at double the intended rate of 5 oz. per bushel.
No form of chemical control was completely effective in suppressing damage but all gave some, and usually a great, improvement, particularly on late-sown or backward crops. Most of the insecticides tested gave closely comparable results. Seed dressings containing at least 40 per cent. heptachlor, dieldrin, aldrin or γ BHC were slightly more effective than combine-drilled insecticidal treatments, with the added advantage of applying only relatively small amounts of persistent insecticides to the soil.
Slight symptoms of phytotoxicity were observed on two sites in 1958 following the use of γ BHC and dieldrin seed dressings applied at the normal rate of 2 oz. per bushel and severe symptoms on two trials in 1959 to seed over-dressed with insecticide and organo-mercury; elsewhere the seed dressings employed appeared to have no adverse effect upon plant establishment.
Dieldrin, aidrin, heptachlor and Thiodan seed dressings behaved similarly in killing a high proportion of larvae within attacked shoots; γ BHC reduced the number of larvae entering the plant, but those which did succeed in entering developed in an apparently normal manner.
On fields where drilling was delayed and the attack severe, the optimum rate of combine-drilled aldrin was probably between 1 and 2 lb. active ingredient per acre. No significant increase in yield was obtained at rates much higher than 2 lb. per acre. While fine-dust formulations gave effective results, the use of a granular fertiliser base improved the flow through the combine-drill and gave increased tillering with slightly higher yields. Heptachlor combine-drilled at 2 lb. active ingredient per acre was slightly superior to aldrin at the same rate.
No adverse effects were recorded when insecticidal seed dressings and combine-drilled aldrin were used together, and at high levels of infestation the double treatment gave increased yields, though insufficient to justify its use on fields having only moderate egg populations.
The biological significance of the attachment of immature stages of Simulium to mayflies and crabs
- Philip S. Corbet
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 695-699
-
- Article
- Export citation
-
It is suggested that the attachment of the immature stages of certain species of Simulidae to mayfly larvae and to crabs is primarily an adaptation whereby the immobile Simulium pupa can obtain protection against disorientation with respect to the current, and against damage, in an environment where available inorganic substrata are liable to be displaced by violent water movement.
The principal evidence for this is that these associations typically occur in fast-flowing streams or rivers, and that the attached stages of Simulium include a disproportionately high number of pupae and large larvae. Any direct benefit the Simulium larvae themselves may derive from the association is regarded as a secondary feature of it.
Certain responses to physical factors, which might be expected in simulium larvae achieving successful attachment, are briefly discussed.
The effect of radioactive phosphorus on the growth and development of Culex pipiens molestus Forsk. (Diptera, Culicidae)
- Albert A. Abdel-Malek
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 701-708
-
- Article
- Export citation
-
In a study of the effect of different concentrations of radioactive phosphorus (32P) in the larval medium on the growth and development of Culex pipiens molestus Forsk., 32P was found to have little noticeable effect on the growth of the larvae up to a concentration of 3·0 microcuries (μc.) of 32P per ml., but, above this concentration, larval growth was greatly retarded.
The period of larval development was increased at concentrations greater than 1·0 μc. of 32P per ml., and pupation occurred two weeks later than in the controls. In concentrations higher than 5·0 μc./ml., pupation was completely inhibited, larvae became sluggish, stopped feeding and finally died.
The effect of 32P in the larval medium on the emergence and radioactivity of the resulting adults was also studied. On the basis of this study, it is recommended that, for efficient utilisation of radio-phosphorus in large-scale field experiments, a concentration of 32P of 1·0 μc./ml. be employed so that emerging adult mosquitos may be sufficiently radioactive to be readily detectable.
Observations on the habits of mosquitos of Plateau Province, Northern Nigeria, with particular reference to Aëdes (Stegomyia) vittatus (Bigot)
- J. P. T. Boorman
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 709-725
-
- Article
- Export citation
-
An account is given of a survey of the mosquitos of the Jos area of Northern Nigeria, during May–June 1960, particular attention being given to those species likely to be concerned with the transmission of arthropod-borne viruses. The area concerned is in the savannah belt at an altitude of about 4,000 ft., with numerous rocky outcrops. The dry season is fairly severe, and extends from about October to May; during this time, drinking water for the villages is obtained from deep wells. At the time of the survey, that is, at the beginning of the rainy season, the most abundant species were Culex univittatus Theo., Aëdes ingrami Edw., A. aegypti (L.), A. africanus (Theo.), A. luteocephalus (Newst.) and A. vittatus (Big.). The biting cycles of these species are illustrated.
A survey was carried out of the breeding habits of A. vittatus in rock holes; those most favoured were about a foot across and six to nine inches deep, and appeared to be of human origin. Larvae appeared rapidly in the holes after the first rains, and predators, particularly dragonfly nymphs and tadpoles, were common in the larger rock holes. Under natural conditions, the duration of the life-cycle was about five days. The survival of the early stages under adverse conditions was investigated in simple laboratory experiments. At normal temperatures, the pupae did not survive desiccation for six hours, and, though the resistance of larvae to drying was not tested fully, it is considered that they are probably no more resistant than are pupae. Eggs survived desiccation for 10 but not for 18 weeks. Water temperature in exposed rock holes was not a factor limiting development, but the temperature of the exposed surface of dry rock holes was such that it appeared unlikely that eggs in these exposed situations would be able to survive the dry season. It was suggested that there may be collections of water in sheltered tree holes or rock holes which support a small but more or less continuously breeding population; this, combined with the ability of the eggs of A. vittatus to withstand desiccation for at least ten weeks at normal temperatures would enable the species to survive the relatively prolonged dry season.
Admixture of malathion and lindane with bagged maize
- W. M. Graham, S. P. L. Kockum
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 727-739
-
- Article
- Export citation
-
An experiment was done in Kenya to test several formulations of lindane and malathion dusts as protectants of bagged maize, with which they were mixed, against reinfestation (post-fumigation infestation) by store pests. The experiment was in the form of a 9 x 9 Latin square employing 162 bags. Sampling initially and after 4 and 5¼ months gave data on bag weight-losses, dust present per bag, numbers of adults of Tribolium castaneum (Hbst.), Oryzaephilus surinamensis (L.), Cadra cautella (Wlk.) and Sitophilus oryzae (L.), and moisture-content changes.
The dust weights (which were expected to be the most reliable measure of treatment efficacy) showed that there was very little difference between malathion admixed at 8, 4 and 2 parts per million. The other six treatments were far less satisfactory and all were significantly different from one another, with the following order of values: lindane at 6, 3 and 1·5 p.p.m., diatomite, kaolin and control. All the other data generally supported these results.
The extreme importance in this experiment of cross-infestation from nearby stacks has been shown in the analysis and has been illustrated by plotting numbers of T. castaneum against dust-weight data. Interpretation of this curve has lent support to work with lindane and malathion published by E. A. Parkin in 1960.
The results emphasise the significance of the contribution of grain and mould metabolism to the total bag weight-losses. Some estimates are made of the savings relevant to the admixture of malathion.
Feeding behaviour of adults of Pieris brassicae (L.) in a laboratory culture
- W. A. L. David, B. O. C. Gardiner
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 741-762
-
- Article
- Export citation
-
Only a few individuals in the first generation of adults of Pieris brassicae (L.) reared in captivity will feed on artificially prepared flowers. By breeding from the eggs laid by these individuals and from a few others which have been helped to feed it is possible to maintain the stock. In each successive generation a few more individuals feed, and after about four generations most of the insects feed voluntarily. Finally, after many generations, all the insects use the flowers, and the experiments described are concerned with this adapted stock.
Many factors influence the attraction of the insects to the artificial flowers and the volume of food taken. Colour, blue or yellow, is responsible for attracting the adults to the flowers, and it is only when they are very close to the flowers and under the stimulus of colour that they show any detectable reaction to the odour of the honey solution in the flowers. Larger blue flowers are more attractive than smaller blue flowers.
The insects find the artificial flowers more easily, at first, if they are high in the cage. More honey solution is taken at 30 than at 20°C. and more in a large cage than in a small cage. When given a choice, the insects take more 10 per cent, (v/v) than 1 per cent, (v/v) honey solution and more 20 per cent, (v/v) solution than 10 per cent, (v/v) solution. When offered two of these solutions in separate cages the insects at first take less of the 1 per cent, solution than of the 10 per cent, solution. Later, presumably in an effort to obtain sufficient nutriment, they take more of the weaker solution than of the stronger solution. The insects live for a much shorter time on the 1 per cent, solution than on the 10 per cent, solution. Fresh honey solution is preferred to a solution 4–5 days old, and older honey solution is quite unsuitable as food. When the survival of adults fed on honey and sucrose solution is compared it is found that females, especially, survive longer when feeding on honey.
About 50 per cent, of the adults fed on 10 per cent, honey solution in the normal stock cage under glasshouse conditions live for 18 days. Very few survive for longer than 36 days. Starved insects all die by the llth day under similar conditions. When starved at 12·5°C. and 60 per cent, relative humidity, about half the males live for 17 to 19 days, but all are dead by about the 23rd day, whereas half the females live for about 29 days and some survive up to 40 days.
The susceptibility of tsetse flies to topical applications of insecticides. II.—Young adults of Glossina morsitans Westw. and organophosphorus compounds, pyrethrins and Sevin
- G. F. Burnett
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 763-768
-
- Article
- Export citation
-
Solutions of six organophosphorus compounds, Sevin, and pyrethrins (alone or synergised with piperonyl butoxide) were applied by microburette in drops of constant volume (0·0216 μl.) to the dorsum of the thorax of young adults of Glossina morsitans Westw., 2–5 days old that had taken their first blood-meal the previous day. The solvents used were decalin (decahydronaphthalene), toluene and lighting kerosene, respectively.
Malathion, methyl-parathion, DDVP (dichlorvos) and Sevin were eliminated in preliminary tests as insufficiently toxic. Muscatox (coumaphos) was reasonably toxic but not readily soluble and was therefore not considered further. Diazinon and Baytex (fenthion) were fully evaluated; the former was about as lethal as DDT, the latter as γ BHC (LD50 about 0·004 μg.). The LD50 of diazinon for males (0·0115 μg.) was significantly smaller than that for females (0·016 μg.) but the LD95 was much the same for both sexes.
Pyrethrins were about equitoxic with dieldrin (LD50, 0·002 μLg.); when synergised with 15 parts of piperonyl butoxide to one of pyrethrins the LD50 for males was reduced to less than half this value, and there was a significant difference in susceptibility of the sexes, the LD50 for females being 1·4 times that for males. However, the slopes of the regression lines were such that at LD95 the difference between synergised and plain pyrethrins was too small to be of any practical use.
These results show that, judged by innate toxicity to young flies, none of these insecticides can compete with dieldrin or Telodrin for practical control, although Baytex is a useful reserve should Glossina acquire resistance to chlorinated hydrocarbons.
A new Australasian species of Elachertus Spinola (Hym., Chalcidoidea, Eulophidae) and notes on two European species
- G. J. Kereich
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 769-772
-
- Article
- Export citation
-
A description is given of a new species of Elachertus, E. agonoxenae (Chalci-Doidea, Eulophidae), on the basis of adults reared from larvae of Agonoxena pyrogramma Meyr. in New Guinea and Agonoxena sp. in Queensland. This species has been imported into Fiji for trial in controlling A. argaula Meyr., a pest of coconut palms. The new species is compared with E. argissa (Wlk.) and E. artaeus (Wlk.), two British species for which lectotypes are here selected.
Observations on the ecology of the cotton flea-beetles in the Sudan Gezira and the effect of sowing date on the level of population in cotton
- E. A. S. La Croix
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 773-783
-
- Article
- Export citation
-
A series of experiments was undertaken to examine the relative concentration of cotton flea-beetles (Podagrica puncticollis Weise and P. pallida (Jacoby), Halticinae) within cotton fields in the Sudan Gezira in 1954 and 1955. Assessments were carried out on the flea-beetle populations and on the damage done by them, and evidence is produced to show that the use of a damage assessment in the first three weeks of the life of the cotton plant is more satisfactory in a large-scale experiment than beetle counts. The assessment lasted for between three and four weeks after the emergence of the seedling cotton.
It appeared that the beetles tended to leave cotton 19 days after sowing. Damage within the cotton field was at first in accord with the sowing differential, but then shifted against this as the flea-beetles moved on to the later-sown cotton as this became more attractive.
The peak population of flea-beetles occurred during the last few days of August and the first few of September when the first-sown cotton was 14–18 days old, and this suffered more damage than the later-sown and less attractive cotton. Differences in the level of attack on the four sowings tended to even out, but did not do so completely as the flea-beetle population was declining.
Observations on Carcelia evolans (Wied.) (Diptera, Tachinidae), a parasite of Diparopsis watersi (Roths.) (Lepidoptera, Noctuidae), in Northern Nigeria
- W. Reed, M. A. Choyce
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 785-793
-
- Article
- Export citation
-
Carcelia evolans (Wied.) is a common parasite of Diparopsis watersi (Roths.) in Northern Nigeria. The egg and early larval stages have not been observed, but the latter are thought to be passed in the larva of the host. The fully grown parasite larva appears to leave its host after the latter has entered the soil and formed its pupal cell, and either immediately before, or after, the host pupates. The parasite puparium is thus formed inside the pupal cell of D. watersi, but outside the host. Before forming its puparium, the parasite larva excavates a pit in the wall of the cell, thus facilitating the subsequent exit of the adult fly, which can push through the weakened cell at this point.
The life-cycle of C. evolans is closely adapted to that of its host, with short-term generations during the cotton season alternating with a long-term, or diapause, generation during the dry season. It is believed that C. evolans goes into diapause as a minute first-stage larva, but the factors that induce diapause are unknown.
The short-term pupal period of C. evolans (12–14 days) was less variable than that of D. watersi (11–31 days) at 27±5°C. In dry conditions, inside and outside the laboratory, the mean duration of diapause for C. euolans (27·3–38·8 weeks) was longer than that of D. watersi (22·9–36·2 weeks). In pupation troughs, approximating to field conditions, the mean duration of diapause in D. watersi (43·2 weeks) was greater than that of its parasite (36·1 weeks). The spreadover of emergence of the parasite from pupation troughs was more regular than that of moths, with no peak in October.
Earlier estimates of the incidence of parasitism at Samaru are probably inaccurate because adult flies have now been shown to be capable of escaping through the apertures of the perforated zinc of the cages then in use. Estimates of the rate of parasitism, made in southern Katsina, showed that 23·1 per cent, of pupal cells obtained at Daudawa between 13th November and 24th December 1959 from cotton that had earlier been treated with insecticidal sprays were parasitised, compared with 30·7 per cent. of those obtained in the same period from unsprayed cotton four miles away. The rate of parasitism was particularly low (16 per cent.) amongst the larvae collected at Daudawa in November, due possibly to the insecticide applications that had been made earlier in the season.
These results imply that the parasite is easier to kill than its host, and an increasing use of insecticides on cotton in Northern Nigeria may therefore adversely affect the degree of control achieved by the parasite.
Teaps in field studies of Glossina pallidipes Austen
- J. P. Glasgow, B. J. Duffy
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 795-814
-
- Article
- Export citation
-
In order to evaluate Morris traps as a method of investigating populations of Glossina pallidipes Aust., and to compare them with fly-rounds, a series of catches was made by both methods in and adjacent to an area of evergreen thicket covering about three sq. miles in the Lambwe Valley, South Nyanza District, Kenya. During the period of the investigations (February 1955-February 1958), the mean monthly apparent density (catches of non-teneral males per 10,000 yd. traversed) determined from a fly-round 5,200 yd. long traversing the thicket varied from 70 to 1,300, and the mean monthly trap catch, determined from 26 traps along a similar traverse but over a shorter period, varied from 190 to 670. Catches by the two methods showed similar fluctuations but were not significantly correlated, and it is not certain that real changes in population occurred. The distribution of G. pallidipes between the three main vegetation communities sampled appeared different when studied by traps, or by other methods (fly-rounds, and searching for resting flies). The two latter methods were in agreement, but traps gave different results, perhaps because one of the vegetation communities may have had a high proportion of productive trapping sites.
Dispersal of G. pallidipes into the surrounding, sparsely wooded grassland was studied by traps arranged in lines extending east and west of the thicket and at right angles to its edge. Traps appeared not to attract flies over a distance as great as 100 yd., but to catch only those that chanced to be in their immediate vicinity. Total catches in three traps over 10 months at distances of 5–100–300–500 and 900 yd. west of the thicket edge were 15,417–965–153–89 and 56, respectively; smaller numbers were taken up to 2,500 yd., the greatest distance investigated. Dispersal was greatest in the wet, cool half of the year.
In catches of G. pallidipes made in six consecutive two-hour periods daily for one year in two batteries, each of seven traps, and on two short fly-rounds, one of each along the east and the other along the west edge of the thicket, the traps yielded 78 per cent, females and the fly-rounds only 17 per cent. There was a marked tendency for females to be caught earlier in the day than males by either method, and for the pattern of catches to be earlier on fly-rounds than in traps. No difference in age, estimated by wing fray, was found between flies caught, by either method, at different times of day.
The total number of G. pallidipes caught by two traps operating 11 hours per day for 10 days at the thicket edge was over four times that caught there concurrently by a stationary party of three men.
It is concluded that traps are valuable because they catch a high proportion of females, thus affording information not given by fly-rounds, and operate continuously, at a higher over-all catching rate than that of men, thus facilitating the study of sparse populations. Nevertheless, site effects and day-to-day variability are both large with traps, so that reproducible results are difficult to obtain.
Index
Index
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. 815-821
-
- Article
- Export citation
Front matter
BER volume 52 issue 4 Front matter and Errata
-
- Published online by Cambridge University Press:
- 10 July 2009, pp. f1-f7
-
- Article
-
- You have access Access
- Export citation