A GOOD deal has been done in recent years to elucidate the laws of animal growth—the rules, that is, which determine that each individual animal grows, develops, and differentiates until its body has reached a certain size, with its various parts and organs in certain proportions and in certain relationships to one another. The deadly precision with which the ‘normal’ result is achieved is so commonplace that we wonder at it less than we do at the much rarer cases when the regulatory mechanism goes wrong. That is the naturalist's instinct. ‘Treasure your exceptions’ is, within reasonable bounds, a sound rule, and the study of unnatural forms of growth is as likely a road as any other to lead us to an understanding of normal development. Of all the varieties of abnormal growth, we know most about tumours, especially of human tumours, and more particularly of those which by their nature tend to kill the individual in which they grow and which we distinguish as ‘malignant tumours’ or ‘cancer.’
John Wright and Sons, Bristol. 1928. Pp. 588.