From the Center for Craniofacial Anomalies and the Department of Orthodontics, University of Illinois. This investigation was supported in part by grants from the National Institute of Health (DE 02872-03) and U.S. Child and Maternal Health.

Presented before the Northern California Component of the Edward H. Angle Society, January, 1972, as partial fulfillment of the requirements for membership.

From the Departments of Anatomy, West Virginia University and the University of Michigan.

Presented before the Midwestern Component of the Edward H. Angle Society, January, 1972.

This paper is based on a thesis submitted for the partial fulfillment of the requirements for the Master of Dental Science degree, the University of Pittsburgh.

Taken in part from a thesis in partial fulfillment of the requirements for the degree of Master of Science, Dentistry, University of Washington, School of Dentistry. This study was supported in part by the University of Washington Orthodontic Memorial Fund.

From the Departments of Orthodontics, Tokyo Medical and Dental Univ. and the Univ. of Illinois.