In consideration of the affections causing absences it has been necessary to depend upon morbidity statistics compiled largely by the United States Bureau pf the Public health and a few summaries from single institutions. The conclusions drawn from the tables and figures included in this paper might give one a concrete conception - allowance must be made since morbidity statistics are difficult to gather and since opinion varies greatly in minor diagnoses and as to extent and severity of illnesses recorded. Several classifications of the causes of absenteeism have been made.