The economics of agroforestry systems can be approached in a purely analytical fashion with mathematical equations and diagrams explaining the principles of analysis. This paper argues that such an approach may be useful for teaching purposes but has little practical relevance. There is an urgent need for a practical tool with which multi-disciplinary teams can assess agroforestry systems. The simplest and most common approaches to the economic analysis of farm management problems are various forms of budgeting. Recent advances in micro-computer technology provide the means by which the principles of partial budgeting can be adapted to the needs of agroforestry taking account of its multiple component nature, seasonal variability and long life span. The paper sets out the specifications for such an approach and indicates how it might be used.

Recognizing the lack of realism in optimal replacement analyses that -me constant prices and yield patterns over time, a stochastic model appropriate to rubber production is developed. Data drawn from Peninsular Malaysia are used to implement the model. The results suggest that efforts should be directed towards establishing bench mark maximum annuities as guides to more economic replanting decisions rather than emphasizing earlier replanting per se. The significance of price stabilization policies also becomes evident.

An increased indoor population of Anopheles sacharovi at the start of hibernation is recorded.Figures are given for dissections of A. sacharovi during the winter months, showing an infectivity rate (sporozoites) of 0·41 per cent.Eggs of A. sacharovi laid at the end of hibernation are described.An account is given of an area in Northern Persia where A. sacharovi is present in association with a lower endemicity of malaria than is usual.We are indebted to Lt.-Col. D. N. Keys, R.A.M.C., Major J. Yofe, R.A.M.C., and Major R. Hillman, R.A.M.C., for their interest and help in these observations.

No abstract

No abstract