Sherwood states that this book was written for medical students and for other persons who have had training in pathogenic bacteriology or inorganic and organic chemistry and who are interested in the underlying principles involved in infection, resistance and diagnostic laboratory tests. It is a nicely arranged, clearly written book, giving plain descriptions of various technical procedures, and is well printed and well illustrated. It has three features which will have great appeal to students: At the end of each chapter is a carefully chosen bibliography referring to the topic under discussion and stimulating wider reading. Near the end of the book is an authors' index which, among other information, gives one a fair idea of the present leaders in the field of immunology. And, finally, there is an excellent subject index, so that any information, from the definition of ablastin to facts about zootoxins, is easily obtainable. On the