Symbiosis: An Introduction to Biological Associations. By V. Ahmadjian & S. Paracer. Hanover: University Press of New England. 15 01 1987 [dated ‘ 1986 ’]. Pp. xii + 212. ISBN 0 87451 371 5. [Available in UK from Trevor Brown Associates, Suite 76–26 Charing Cross Road, London WC2.] Price £26 ($US39.50). - The Biology of Symbiosis. By D. C. Smith & H. E. Douglas. London: Edward Arnold. [A series of Student Texts in Contemporary Biology, H. J. Willis & M. A. Sleigh, eds] 5 02 1987. Pp. xi + 302. ISBN 0 7131 2939 5. Price £16.95 (soft-bound).