There is no book - there can be no book - that will infallibly point the way to successful bloodstock breeding. Yet in the ''General Stud Book'', the sport of horse racing has produced a genetic record extending over more than two centuries and a score of generations that contains an ordered store of facts about the hereditary qualities of one living species - data that no scientific body possesses. Here is the recorded experience of the man who, above all others of our time, has deciphered the riddle of its manifold pages: Federico Tesio. Tesio and Nearco and Ribot are the names of the greatest breeder, the outstanding sire, and the most consistent winner of the twentieth century, and perhaps of all time. The astonishing and prolonged success of the Italian stud at Dormello was the result not merely of an encyclopaedic knowledge of recorded facts about equine dynasties and the history of the thorough bred but of wide practical experience in all parts of the world and acute, sustained and minute observation of the characteristics of particular horses and bloodlines. The essence of Tesio's philosophy and something of his genius has been distilled into this gem of a book.