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Notes: Summary Fertilized eggs ofHodotermes mossambicus took up water progressively during the last 15–16 days of the 24–25 day incubation period. Both the large eggs from founding pairs and the small eggs from mature colonies approximately doubled in weight. Infertile eggs, 50% of which survived for 14 days, showed a lower rate of water uptake. The eggs could take up water when they were in contact with the liquid. Under subsaturated conditions, the reproductives provided the liquid while tending the eggs, but in contact with free water the eggs could still maintain their water balance in the absence of the reproductives. However, tending was essential for the eggs to survive, even in the presence of free water.

Notes: Summary The distribution of cellulase activity in the guts of workers of the termiteT. trinervoides was investigated. Approximately 70% of the total activity was found in the midgut and about 40% oif this occurs in the midgut wall. The appearance and distribution of gut bacteria is described. It is concluded that, in this species, the cellulase is synthesised by the termites themselves.

Notes: Abstract The components of trail-laying and trailfollowing behaviour in the harvester termitesHodotermes mossambicus (Hagen) andTrinervitermes trinervoides (Sjöstedt) were investigated. In both species the trails are laid by pressing the third to sixth abdominal segments against the substratum. The trails are detected by olfactory receptors which are found on the antennae—principally on the distal one third.H. mossambicus trails andT. trinervoides trails laid on paper persisted for approximately 90 and 20 minutes respectively at 23° C±1° C. T. trinvervoides trail substances were steam volatile, but steam distillates ofH. mossambicus individuals were inactive. Ethanol or diethyl ether extracts ofH. mossambicus were, however, active. The volatile components of the secretions of the nasuteT. trinervoides soldiers were collected by drawing an air shtream over fighting colonies and passing it through gas scrubbing bottles containing appropriate solvents.

Notes: Abstract The control of caste formation in the harvester termiteHodotermes mossambicus (Hagen) was investigated. Normal laboratory colonies contained a primary reproductive pair, between 6.59 and 24.98% workers, 0.39 and 3.45% soldiers and 74.64 and 92.06% larvae. Supplementary reproductives did not develop in colonies deprived of their king and queen. Continuous removal of soldiers stimulated soldier production. We have suggested that a pheromone produced by the soldiers plays a major role in controlling the soldier population of a colony. A similar phermone system appreared to control the production of workers. Evidence was also obtained that the primary reproductive pair influenced the production of workers and soldiers.

Notes: Two patients who developed sleep apnoea following upper cervical cord surgery are described. The underlying mechanisms and management of the sleep apnoea syndrome are discussed.

Notes: The design of randomized controlled trials to assess the efficacy of pharmacological measures for the prevention of the gastrointestinal side-effects of anti-inflammatory drugs requires an accurate estimate of excess risk under controlled conditions. Photocopies of 952 randomized controlled trial publications were obtained after scanning titles and abstracts of a MEDLINE computer search, 427 were excluded for obvious reasons, and 525 were again photocopied after obliterating source and results. Selection criteria were: the presence of a non-anti-inflammatory drug control group; at least 4 days of therapy; at least 3 days without anti-inflammatory drugs before randomization; no complicating background drugs; mention of side-effects; and a clear differentiation of gastrointestinal complications. Observer error, with two independent readings, for inclusion suitability in the study was 19% for Methods and 9% for Results. For the 44 aspirin trials, the mean therapy duration was 357 days; the unweighted rate difference between therapy and control groups (± 1 S.E.M.) for ulcer was 0.006 ± 0.003, for gross haemorrhage 0.006 ± 0.002 and for unspecified gastric symptoms 0.03 ± 0.01. In 123 non-aspirin non-steroidal anti-inflammatory drug (NA—NSAID) trials, the mean duration was 67 days; the unweighted rate difference for ulcer was 0.0005 ± 0.0003, for gross haemorrhage 0.007 ± 0.004 and for unspecified gastric symptoms 0.02 ± 0.005. Risk differences were also pooled using the DerSimonian and Laird method, which weights studies inversely according to variance. Using this method, only the unspecified gastric symptoms for non-aspirin non-steroidal anti-inflammatory drugs (NA—NSAIDs) and the haemorrhage for aspirin were found to be statistically significant. Longer studies have higher risk differences. Randomized control trials to determine prophylactic efficacy against haemorrhage (that is, to demonstrate a reduction of ulcer rate in the therapy group to the rate of controls) would require 190 patients in each group for NA—NSAIDs in studies of 2–6 months; 950 subjects would be needed to detect a 50% reduction. Randomized control trials to determine a reduction in ulcer rate to that of controls in patients on aspirin for more than 6 months would require 700 subjects in each group; 3346 subjects would be needed to detect a 50% reduction. Such studies are feasible.