Eighty-eight fetuses varying from 7-40 wks. in menstrual age were examined. No activity was observed in the 7, 7 1/2 and 8 wk. old fetuses. The first response to tactile stimulation was secured in a fetus slightly over 8 wks. of menstrual age. The region first susceptible to stimulation is the upper lip and ala of the nose. Spontaneous movements were observed to occur first at 9 wks. of fetal age. At 14 wks. of age the fetus exhibited most of the reflexes of the new-born infant with the exception of respiration, use of the voice, grasping, the sucking response, tendon reflexes and special sense organ responses.