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The legal regulation of plant protection products (Dir. 91/414/ EEC) is a bottleneck in the market introduction of new microbial biocontrol agents, plant extracts and pheromones. In contrast, invertebrate biocontrol agents (“beneficials”) are not registered at EU level. The EU-funded project REBECA suggested improvements to accelerate the regulation process and make it more cost-effective, without compromises to the level of safety. Representatives of all stakeholder groups participated in the REBECA workshops. The EU Commission and Member States are encouraged to improve the registration of biocontrol organisms, plant extracts and semiochemicals at EU and/or national level. The full proposals can be found at www.rebeca-net.de.

The legal regulation of plant protection products (Dir. 91/414/ EEC) is a bottleneck in the market introduction of new microbial biocontrol agents, plant extracts and pheromones. In contrast, invertebrate biocontrol agents (“beneficials”) are not registered at EU level. The EU-funded project REBECA suggested improvements to accelerate the regulation process and make it more cost-effective, without compromises to the level of safety. Representatives of all stakeholder groups participated in the REBECA workshops. The EU Commission and Member States are encouraged to improve the registration of biocontrol organisms, plant extracts and semiochemicals at EU and/or national level. The full proposals can be found at www.rebeca-net.de.

The legal regulation of plant protection products (Dir. 91/414/ EEC) is a bottleneck in the market introduction of new microbial biocontrol agents, plant extracts and pheromones. In contrast, invertebrate biocontrol agents (“beneficials”) are not registered at EU level. The EU-funded project REBECA suggested improvements to accelerate the regulation process and make it more cost-effective, without compromises to the level of safety. Representatives of all stakeholder groups participated in the REBECA workshops. The EU Commission and Member States are encouraged to improve the registration of biocontrol organisms, plant extracts and semiochemicals at EU and/or national level. The full proposals can be found at www.rebeca-net.de.

Hydrologists and ecologists studying tundra ecosystems have worked largely independently, with little cross-fertilization between disciplines. Their disciplines are, however, inextricably linked by a need to understand the dynamics and significance of the common substance water, in its liquid, solid and gaseous state within tundra environments. The impacts of predicted long-term changes in climate have particularly important consequences for the functioning of tundra systems and there is a pressing need to initiate studies that integrate hydrological and ecological methodologies and concepts. Our paper attempts to summarize existing information on the role of water within tundra ecosystems, to emphasize the fundamental links between the biotic and the physico/chemical environments and to suggest how a closer integration of ideas might be achieved. Given the breadth of the subject matter the paper is intended to be illustrative rather than comprehensive. The paper examines the physical impacts of water in its various states on the tundra environment, emphasizing in particular the causes of spatial variation in water availability to living organisms. The significance of water is discussed for a range of organism groups, including plants, invertebrates and microorganisms and its pivotal role in ecosystem function and disturbance stressed. The need to develop integrated hydological/ecological models for tundra systems on different spatial scales is emphasized.

Hydrologists and ecologists studying tundra ecosystems have worked largely independently, with little cross-fertilization between disciplines. Their disciplines are, however, inextricably linked by a need to understand the dynamics and significance of the common substance water, in its liquid, solid and gaseous state within tundra environments. The impacts of predicted long-term changes in climate have particularly important consequences for the functioning of tundra systems and there is a pressing need to initiate studies that integrate hydrological and ecological methodologies and concepts. Our paper attempts to summarize existing information on the role of water within tundra ecosystems, to emphasize the fundamental links between the biotic and the physico/chemical environments and to suggest how a closer integration of ideas might be achieved. Given the breadth of the subject matter the paper is intended to be illustrative rather than comprehensive. The paper examines the physical impacts of water in its various states on the tundra environment, emphasizing in particular the causes of spatial variation in water availability to living organisms. The significance of water is discussed for a range of organism groups, including plants, invertebrates and microorganisms and its pivotal role in ecosystem function and disturbance stressed. The need to develop integrated hydological/ecological models for tundra systems on different spatial scales is emphasized.

We tested the hypothesis that habitat temperature is the driving variable determining both the short-term and seasonal patterns of abundance (biomass) of Eying adult non-biting midges (Chironomidae) in the high Arctic. Malaise traps were used to record the Eight activity patterns of adult chironomids during the 1992 and 1993 seasons at two contrasting sites, a polar semi-desert and a tundra heath adjacent to Ny Angstrom lesund, Spitsbergen, Svalbard. The relationship between flight activity, measured as chironomid biomass captured, and macro and microclimatic parameters was examined. Mean and minimum screen temperatures were the best single predictors of chironomid activity. Best subsets regression was used to establish predictive relationships between biomass captured and climatic parameters for each site. Again, macroclimatic temperature variables emerged as the best predictors, together with much smaller contributions from relative humidity and precipitation. The species composition of the chironomid community changed as the summer progressed and the 'average' individual became smaller. However, when cumulative biomass captured per trap was plotted against cumulative day degrees above zero, starting at snow melt, the relationship on both sites in 1992, an average year, was approximately linear or at most slightly curved. This suggested that biomass capture was mainly a function of temperature and time. By contrast, in 1993, the warmest year on record (1961-93), the initial response was again almost linear but later became asymptotic, suggesting that the supply of chironomids available for capture was depleted, despite suitably high temperatures. This contrast between years (100 day degrees) provided an opportune analogue for the likely effects of climate warming on chironomid activity. The implications for the food supply of tundra-breeding birds are discussed in the context of the known emergence patterns of Arctic chironomids

An experiment was conducted to measure the effects of summer warming on the total population densities of soil-dwelling microarthropods in the high Arctic and to compare these results with those from natural between-year and between-site variations. Small polythene tents were used to elevate summer temperatures over 3 years on polar semi-desert and tundra heath in West Spitsbergen, Svalbard, Norway. Soil cores were taken at regular intervals from tented and untented (control) plots and heat extracted for mites (Acarina: Oribatida) and springtails (Collembola). Species present were similar at both sites, but at the start of the experiment total springtail populations were greater at the polar semi-desert whilst oribatid mite densities were equal at both sites. No significant effect of temperature elevation on oribatid mite populations emerged, even after 3 years. By contrast, springtail numbers were significantly lower on tented versus control plots at the polar semi-desert at the end of year 3, but not so at the tundra heath. Collembola numbers declined at both sites during the warm dry midsummers of 1992/1993 and this was most marked at the better drained polar semi-desert site. Over the equivalent period total oribatid mite populations, while relatively more stable, increased significantly at the polar semi-desert as a result of an increase in the number of juveniles. Results are interpreted in the context of the ecophysiological adaptations of oribatid mites and springtails to soil temperature and moisture. The resulting survival characteristics are considered in relation to the temperature and moisture characteristics of the two sites. The experiment demonstrated that year to year variation in climate, interacting with physical differences between sites, produced an equal or greater effect on microarthropod numbers at any one site than the 8–10% increase in “heat availability” (day degrees above zero) resulting from the summer tent treatment. The limitations of

We tested the hypothesis that habitat temperature is the driving variable determining both the short-term and seasonal patterns of abundance (biomass) of Eying adult non-biting midges (Chironomidae) in the high Arctic. Malaise traps were used to record the Eight activity patterns of adult chironomids during the 1992 and 1993 seasons at two contrasting sites, a polar semi-desert and a tundra heath adjacent to Ny Angstrom lesund, Spitsbergen, Svalbard. The relationship between flight activity, measured as chironomid biomass captured, and macro and microclimatic parameters was examined. Mean and minimum screen temperatures were the best single predictors of chironomid activity. Best subsets regression was used to establish predictive relationships between biomass captured and climatic parameters for each site. Again, macroclimatic temperature variables emerged as the best predictors, together with much smaller contributions from relative humidity and precipitation. The species composition of the chironomid community changed as the summer progressed and the 'average' individual became smaller. However, when cumulative biomass captured per trap was plotted against cumulative day degrees above zero, starting at snow melt, the relationship on both sites in 1992, an average year, was approximately linear or at most slightly curved. This suggested that biomass capture was mainly a function of temperature and time. By contrast, in 1993, the warmest year on record (1961-93), the initial response was again almost linear but later became asymptotic, suggesting that the supply of chironomids available for capture was depleted, despite suitably high temperatures. This contrast between years (100 day degrees) provided an opportune analogue for the likely effects of climate warming on chironomid activity. The implications for the food supply of tundra-breeding birds are discussed in the context of the known emergence patterns of Arctic chironomids

An experiment was conducted to measure the effects of summer warming on the total population densities of soil-dwelling microarthropods in the high Arctic and to compare these results with those from natural between-year and between-site variations. Small polythene tents were used to elevate summer temperatures over 3 years on polar semi-desert and tundra heath in West Spitsbergen, Svalbard, Norway. Soil cores were taken at regular intervals from tented and untented (control) plots and heat extracted for mites (Acarina: Oribatida) and springtails (Collembola). Species present were similar at both sites, but at the start of the experiment total springtail populations were greater at the polar semi-desert whilst oribatid mite densities were equal at both sites. No significant effect of temperature elevation on oribatid mite populations emerged, even after 3 years. By contrast, springtail numbers were significantly lower on tented versus control plots at the polar semi-desert at the end of year 3, but not so at the tundra heath. Collembola numbers declined at both sites during the warm dry midsummers of 1992/1993 and this was most marked at the better drained polar semi-desert site. Over the equivalent period total oribatid mite populations, while relatively more stable, increased significantly at the polar semi-desert as a result of an increase in the number of juveniles. Results are interpreted in the context of the ecophysiological adaptations of oribatid mites and springtails to soil temperature and moisture. The resulting survival characteristics are considered in relation to the temperature and moisture characteristics of the two sites. The experiment demonstrated that year to year variation in climate, interacting with physical differences between sites, produced an equal or greater effect on microarthropod numbers at any one site than the 8–10% increase in “heat availability” (day degrees above zero) resulting from the summer tent treatment. The limitations of

Arthropods, as poikilotherms, adapt to cold environments in a variety of ways that include extension of locomotory activity to low temperatures, enhancement of metabolic rate and maintenance of a positive energy balance whenever possible. The ecological implications for many such animals are extension of the life cycle and a requirement for an individual to overwinter several times. Prolonged sub-zero temperatures increase the risk of tissue freezing, and two main strategies have been evolved, first avoidance of freezing by supercooling, and secondly, tolerance of extracellular ice. In the first strategy, freezing is invariably lethal and extensive supercooling (to — 30 °C and below) occurs through elimination or masking of potential ice nucleators in the body and accumulation of cryoprotective substances such as polyhydric alcohols and sugars. Such species are termed freezing intolerant. The second strategy, freezing tolerance, is uncommon in arthropods and other invertebrates, and usually occurs in a single life stage of a species. Freezing of liquid in the extracellular compartment is promoted by proteinaceous ice nucleators. Freezing is therefore protective, and the lethal temperature is well below the supercooling point in freezing tolerant individuals, whereas in most freezing intolerant species it is close to or at the supercooling point. Proteins also act as antifreezes in insects of both strategies, producing a thermal hysteresis by lowering the freezing point of haemolymph in a non-colligative fashion while not affecting the melting point temperature. Recent studies and developments in arthropod cold tolerance are discussed against this background, and a broader approach than hitherto is advocated, which integrates ecological information with physiological data.

Arthropods, as poikilotherms, adapt to cold environments in a variety of ways that include extension of locomotory activity to low temperatures, enhancement of metabolic rate and maintenance of a positive energy balance whenever possible. The ecological implications for many such animals are extension of the life cycle and a requirement for an individual to overwinter several times. Prolonged sub-zero temperatures increase the risk of tissue freezing, and two main strategies have been evolved, first avoidance of freezing by supercooling, and secondly, tolerance of extracellular ice. In the first strategy, freezing is invariably lethal and extensive supercooling (to — 30 °C and below) occurs through elimination or masking of potential ice nucleators in the body and accumulation of cryoprotective substances such as polyhydric alcohols and sugars. Such species are termed freezing intolerant. The second strategy, freezing tolerance, is uncommon in arthropods and other invertebrates, and usually occurs in a single life stage of a species. Freezing of liquid in the extracellular compartment is promoted by proteinaceous ice nucleators. Freezing is therefore protective, and the lethal temperature is well below the supercooling point in freezing tolerant individuals, whereas in most freezing intolerant species it is close to or at the supercooling point. Proteins also act as antifreezes in insects of both strategies, producing a thermal hysteresis by lowering the freezing point of haemolymph in a non-colligative fashion while not affecting the melting point temperature. Recent studies and developments in arthropod cold tolerance are discussed against this background, and a broader approach than hitherto is advocated, which integrates ecological information with physiological data.

Page 8 signed in letterpress: Barbara Leigh Smith Bodichon. Printer's statement from colophon., Athenaeum copy bound with: Bodichon, Barbara Leigh Smith. Reasons for the enfranchisement of women. London, 1866, OBJECTIONS TO THE ENFRJ\NOHISEMEN'l1 OF ~VO~IEN CONSIDERED. BY ~IRs. B. ODICHON. .. • 2, WARRINGTON CRESCENT, LONDON, \V. 1866. Price One Penny . . ' OBJECTIONS TO THE ENFRANCI-IISEl\IENT OF \VOl\fEN CONSIDERED. T~1e follo\\ring Petition was presented to Parlia­ment on June 7th, 186G :- " Tlte humble Petition of lite undersigned, sltewetlt,- " That it having been expressly laid down by high autl1oritics that the possession of property in this country carries with it the right to vote in the election of representati\'es in Parliament, it is an evident anomaly that some holders of property are allowed to use thid right, while others, forming no less a constituent part of the nation, and equally qualified by law to hold property, arc not nulc to exercise this privilege. '' That the participation of women in the government is consis­tent with the principles of the British Constitution, inasmuch as women in these islands have always been held capable of sovereignty, and women arc eligible for various public offices. "Your petitioners therefore humbly pray your honourable !louse to consider the expediency of providing for the representa­tion of all householders, without distinction of sex, who possess such property or rental qualification as your IIonourable !louse may determine." This petition "\vas signed by 1499 women, including many whose names alone are sufficient to entitle them to a r espectful hearing. It has given rise to discussion in many households, and articles have appeared in ne\vspapers and magazines, some con­taining arguments for the prayer of the petition and some against it. As I think the onus of proof lies with those who say women ought not to vote, I will proceed to consider the arguments I have met with on that side of the question. Among these, the first and commonest is,-W omen do not want votes. Certainly that is a capital reason 'Yhy women should not have votes thrust upon them, and no one proposes compulsory registration. There are many men wb