Icterus gravis of the new-born is a term which has in the past been used rather indiscriminately to describe any severe form of jaundice of unknown or doubtful origin occurring in a new-born infant. If one excepts from this classification the types of jaundice due to sepsis, congenital syphilis or congenital malformation of the bile ducts, one is left with a group of cases in which a complete understanding of the underlying process is often lacking. For several years we have been making a study of patients with such a condition, and the results of the work are the subject of this communication.
The consensus is that physiologic icterus neonatorum is a retention jaundice due primarily to hemolysis, which takes place in all new-born infants. It is a moot point whether jaundice results in all cases of excessive hemolysis or only in those cases in which there is a temporary