Diagnostic Pathways in Clinical Medicine. An Epidemiological Approach to Clinical Problems, by B. J. Essex. 173 pages, illustrated. Churchill Living-stone, 19 West 44th Street, New York, N.Y. 10036. 1977. $9.95 (paper bound).

Doing Better and Feeling Worse, by John H. Knowles. 287 pages. W. W. Norton & Co., 500 Fifth Avenue, New York, N.Y. 10036. $9.95 cloth; $3.95 paper.

Festschrift in Honour of C. A. Hoare, F.R.S. on the Occasion of His 85th Birthday. Protozoology, Volume 3. 199 pages, illustrated. Published by London School of Hygiene and Tropical Medicine; distributed by Wm. Dawson & Sons Ltd., Cannon House, Folkestone, Kent, England. 1977. £5.00.

Introduction to Animal Parasitology, 2nd edition, by J. D. Smyth. xiv + 466 pages, illustrated. Halsted Press, 605 Third Avenue, New York, N.Y. 10016.