These lectures are largely devoted to an exposition of Pavy's original views concerning carbohydrate metabolism. He opposes vigorously the generally-accepted doctrine, developed from Bernard's researches, that glycogen represents a resting stage in the metabolism of sugar. Glycogen, according to Pavy, is not normally converted again into sugar; indeed, he considers that carbohydrates do not normally enter the cireulation from the intestine, but are converted by the lymphocytes into proteid and by the intestinal epithelium into fat. It can not be said that the discussion of the topic in this book is either strikingly lucid or convincing. Although Pavy has now, for some time, been urging his views, they are not generally accepted by physiologists and chemists as having overthrown the long-established view that glycogen is converted normally into sugar whenever the quantity in the blood has been reduced below normal through its combustion in the muscles and other active tissues.