“…In an attempt to provide a more controlled environment Moscona introduced the use of rotating culture vessels. Moscona and his associates have utilized this system to study the relationship of embryonic age, developmental state, environmental factors, and spdcific tissue components on the formation of such reaggregating complexes (Orr, 1968;Lilien, 1968;Garber, 1967). Recently ' several laboratories have applied the rotation culture technique to questions of biochemical and histological maturation of mammalian brain.…”