Standards for measurements used in appraisal of growth during the first year of life are ordinarily derived from infants born at term and thus do not reflect the conditions of the extremely important segment with birth weights under 5 lb. (2,270 gm.). The dearth of information concerning growth of the head has been especially felt as more attention is focused on early recognition and relief of hydrocephaly, subdural hematoma, and other lesions manifested by increase in intracranial bulk. Material available at the Children's Hospital of Michigan has consequently been studied with reference chiefly to variations in head circumference and the relation of this dimension to increasing body length.
Figures at birth were obtained for over 1,000 consecutive infants admitted to the premature nursery. Subsequent data were obtained from that portion of the nursery group followed in the premature clinic of our outpatient department. Gross disproportions and obvious errors in