The occurrence of two cases of recurrent vomiting in members of the same family, a brother and sister, is my apology for offering the following report:
Case 1.
—The elder of the patients is a boy of 7, rather small, as his parents are, but active and vigorous, though of a distinctly neurotic disposition. He was delivered at term by instruments, and nursed for six weeks with poor success. From that time on he passed through the hands of various physicians, who tried in vain to find a suitable milk modification. During this time he was constantly subject to vomiting, colic and indigestion. Measles and whooping-cough have been his only other sicknesses. The mother, who is a keen observer, thinks that the child has always had this type of vomiting, because of its severity and associated prostration. It was not until the boy was in his fifth year, however, that acetone