The medical literature has many excellent case reports and several good treatises on perforation of the gastrointestinal tract of the newborn infant, but the articles are scattered in specialized journals, or the cases are listed under such obscure titles in the indexes (peptic ulcer, fetal peritonitis, melena neonatorum, pneumoperitoneum or meconium peritonitis) that it is a tedious procedure even to locate the references. I have attempted to bring together in the accompanying table all of the cases of spontaneous perforation regardless of cause, but in view of the varied approaches to the condition 1 or more cases may have been overlooked. Cases of perforation associated with definite obstruction of the bowel, intrinsic or extrinsic, are not included ; cases of intrauterine rupture of the appendix have also been omitted (Abt,1 Jackson,2 Hill and Mason3).Perusal of the literature also revealed that authors differed in their interpretations of what constitutes a rupture. In some series are included cases of ulceration through the layers of the bowel, whether or not the serosa was finally penetrated. In others are included only the cases of rupture into the free abdominal cavity. As various degrees of ulcération may occur and as microscopic sections would be necessary to enable one to determine the exact extent of involvement in some instances, it has seemed logical to classify as cases of perforation only those in which the lesion actually perforated the entire wall, including the serosa. However, all such cases even though the perforation was walled off and not associated with general peritonitis, are included.The original purpose of limiting the study to newborn infants has not been adhered to slavishly. Only newborn patients are listed in the