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Although the histology of the adrenal gland of many mammals, particularly domestic animals, is known, the histology of that of the African buffalo, Syncerus caffer, has not been described previously. Tissue from seven male and female adult buffalo was processed for light and electron microscopy. The gland is surrounded by a connective tissue capsule which contains smooth muscle fibres. The cortex of the gland is divided into three distinct zones with the cells of the outer zone being arranged in arcades rather than in glomeruli. The cells of this zona arcuata and of the outer region of the fasciculata have features typical of steroid-producing cells. The inner part of the fasciculata is a broad, less vacuolated and more intensely stained region than the outer region. Cells of the zona reticularis are arranged in freely anastomosing cords and are less vacuolated than the arcuata and the outer part of the fasciculata. The medulla is characterized by two distinct regions: an outer region of cells with granules of varying electron density which do not stain specifically with the Masson-Fontana technique and an inner zone of cells containing intensely electron dense granules which are chromaffin positive. These cells are adrenaline- and noradrenaline-secreting cells, respectively. The structure of the gland is thus typical of that of other mammals.

The histology, particularly the ultrastructural cytology, of the adrenal gland of the African elephant, Loxodonta africana, is virtually unknown. Tissue from 14 adult male and female elephants was processed for light and transmission electron microscopy. The gland is surrounded by a thick capsule composed of an outer layer of dense connective tissue and an inner layer in which smooth muscle fibres predominate. Below the layer of smooth muscle, a continuous layer of relatively undifferentiated ‘capsular’ cells occur. Where the capsular cells abut on the zona glomerulosa, they appear to be differentiating into glomerulosa cells, as small lipid droplets are present in their cytoplasm. The cortex is divided into three zones as is found in the adrenal glands of other mammals. Large amounts of collagenous and reticular tissue support the secretory cells, which have a marked lipid content. With electron microscopy, the cortical cells show features typical of steroid-producing cells. The medulla is characterized by an outer region of pale-staining chromaffin-positive (adrenaline) cells and an inner region of intensely staining chromaffin-positive (noradrenaline) cells. The latter cells contain granules of different sizes and structure.

Book Review 1Book Title: Physiological Function in Special EnvironmentsBook Author: Edited by Charles V. Paganelli & Leon E. FarhiSatellite Symposium of the American Physiological Society Fall Meeting (1985). Springer:Verlag New York Inc.Book Review 2Book Title: Parasitic DiseasesBook Author: M. Katz, D.D. Despommier & R. Gwadz Second edition, Springer-Veriag, 1988. 301 pages.Book Review 3Book Title: The Unheeded Cry - Animal Consciousness, Animal Pain, and ScienceBook Author: Bernard E. Rollin Published by the OUP. 308 pages.

Blood composition was investigated in anaesthetized elephant and Buffalo and in elephant immobilized by succinyldicholine. Results obtained indicate that data from undisturbed animals shot in the brain closely approximate the situation in anaesthetized animals, except for blood-gas composition. Cortisol concentrations increase after anaesthetization and then decrease again, suggesting that the procedures involved are experienced to some extent as physiological stress. In the case of animals paralysed by succinyldicholine, Cortisol and blood-gets results suggest that when this substance is used in culling procedures, elephant should be killed by a shot into the brain within 16 min after darting.

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The haematology of the mudfish (Labeo umbralus) has been studied in the laboratory and in the wild state. Significant differences between laboratory and field data and also between field data obtained for fish from different localities were observed in several of the parameters studied and the results are considered in relation to the validity of extrapolation of laboratory data to field conditions.

Various haematological parameters of carp blood were examined on a monthly basis from February to November. Seasonal variations were observed in red and white blood cell counts, in haemoglobin and plasma protein concentrations and in mean corpuscular fragilities. Sexual differences were evident in red blood cell counts, haematocrit values and haemoglobin concentrations. Plasma protein electrophoresis showed marked conformational changes during the study period. The results are discussed in relation to previous findings and also in relation to the use of blood as a possible indicator of breeding season in carp.

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It may be considered unfair to respond to a paper from the point of view of another discipline, especially if central issues or assumptions in that article are discussed critically. In this paper, comments are made on Alistair Chadwick’s paper from the point of view of philosophy and ethics, but these are offered in the spirit of a constructive dialogue across narrowly conceived disciplinary borders. The general theme of these comments also calls for interdisciplinary dialogue: the language that we use in our debates about environmental education, ethics and action. As such, language is a themeabout which every discipline in the social sciences can make a meaningful contribution, and this is what I would like to offer here.In this Viewpoint I will focus on only one issue, namely certain problems that may arise if we accept the language in which Chadwick speaks in his paper about ‘sustainable development’ and ‘values’ respectively. I will raise a number of critical points in this regard, not because there is one and only one appropriate language within which we can discuss our environmental concerns and our (educational) responses to them, but rather because we should be self-consciously aware of the assumptions and implications hidden in the language that we choose to discuss these matters, thus enabling us to disect and evaluate these assumptions and implications with a view to determine to what extent they enhance or undermine our efforts to understand the nature and extent of the environmental challenges that we are faced with.