Few common disturbance in infancy are so distressing to members of the immediate family, so puzzling and worrisome to the physician and nurse but so free from untoward consequences to the patient as the paroxysms of so-called colic. The majority of babies have more or less of this during the first two to five months of life, a time which might well be called the hypertonic period of early infancy. In actual practice it has been found that time-honored household remedies are ineffective, and the practitioner has not always found it simple to furnish relief. However, medical treatment and the maintenance of a special regimen can be entirely successful. The handling of truly neuropathic infants will require a somewhat different procedure. NORMAL BEHAVIOR IN NEWBORN PERIOD The newborn infant begins with those behavior patterns which persist from fetal life, namely, inborn reflexes. He acquires new patterns, sometimes designated as conditioned