COLLARD, ROBERTA R. Exploratory and Play Behaviors of Infants Reared in an Insitution and in Lowerand Middle-Class Homes. CHILD DEVELOPMENT, 1971, 42, 1003-1015. Number of exploratory and play responses and varieties of schemas shown to a toy and performance on the Gesell Cubes and Cup and Cubes subtests were compared in institutional infants (8.5-13 months old) and lower-class and middle-class home-reared infants matched in age and sex to the institutional Ss. Institutional babies were found to explore less and to show fewer schemas and less social play than did home-reared babies. The Ss from lower-class homes explored as much as those from middle-class homes, but middle-class-home babies showed more schemas and more social play than did the former. The babies' level of performance on the Gesell subtests appeared to depend on their experience with similar objects and on the extent to which someone had played with them.