About four years ago I undertook a study of icterus neonatorum by means of the duodenal catheter,1 for it seemed as if a method of obtaining bile at the site of entry into the intestine offered advantages over methods hitherto employed. Accordingly a considerable number of infants, some 124 in all, were tested by this means, and observations were made as to the onset of the excretion of bile in the new-born, its relation to the intake of colostrum, and especially as to its association with jaundice. The details of the various cases comprising this investigation will be found in the paper referred to. The results may be broadly summarized in a short table (Table 1).
In order to determine the onset of the excretion of bile, tests were carried out day after day for a period of several days on each infant, the aspiration being continued for two