TheAnatomicalRecord Aaron J. Ladman, Editor Department of Anatomy Mail Stop 408 Hahnemann University Broad & Vine Philadelphia, Pennsylvania 19102 ASSOCIATE EDITORS G. Adolph Ackerman Ohio State liniversity Peter S. Amenta Robert W"od Johnson Medical School J o h n V. Basmajian Chrdokc Rehabilitation Center >McMastcrI Jniversi t y D a l e E. B o c k m a n Medical College of Georgia Robert P. B o l e n d e r h i v c r s i t y o f Wdshington Robert S. Bressler New York <:allege of Podiatric Medicine Ruth EUen Bulger Institute of Medicine Washington, D <:. Margaret R. Byers Cniversity of Washington Edward C. Carlson lhiversity of North Dakota Nikolajs Cauna llniversity of Pittsburgh D o n a l d J. Donaldson Webster S.S. J e e University of Tennessee Memphis University (if CJtah Harvard Medical School Ernst Kallenbach Thomas S. R e e s e Martin Dym Georgetown University University of Florida Gainesville Gordon 1. Kaye Albany Medical College Robert 0. KeUey T h e University of New Mexico Barry F. King University of California Davis National Institutes of Health Paul J. Reier IJniversity of Florida Stanley L. Erlandsen University of Minnesota Medical School Richard A. Ellis Brown 1Jniversity J o h n F. Fallon University of Wisconsin D o n a l d A. Fischman Cornell Liniversity Medical College Dr. Jef€rey T. Laitman Charles J. Flickinger llniversity of Virginia Daniel S. Friend llniversity of California San Francisco Geraldine F. Gauthier T h e University of Massachusetts Michael D . G e r s h o n Columbia University B e n R. Clower Jack L. Haar llnivcrsity of Mississippi Jackson Medical College of Virginia William G. Dail, Jr. T h e l'nivcrsity o f New Mexico D e n n i s M. D e Pace Hahncmann 1:niversity Richard D . Dey West Virginia 1:niversity New York llniversity Liida Saland Health Science Center at Dallas I'niversity o f Galifornia San Francisco Jack Rosenbluth T h e University of New Mexico Gary S c h o e n w o l f University of Utah Arlen R. Severson University of Minnesota Duluth !A)yola llniversity School of Medicine Gerald R. C u n h a Lynn J. RomreU llniversity o f Floridl Gainesville Medical University of South Carolina J o h n Clancy, Jr. T h e llniversity o f Texas Mcdical Branch at Galveston Gainesvi 1It. Eric R. Lacy Madison William J . Gonyea T h e University of Texas Richard E. CoggeshaU Elio Raviola Duane E. Haines 'University of Mississippi Jackson D a m o n C. Herbert T h e Miversity of Texas at San Antonio J o h n C. Herr University of Virginia Robert Hiklda Ohio University David E. H i n t o n University of California Davis Manuscripts and illustrations intended for publication in The Anatomical Record should be sent to Dr. Aaron J. Ladman, Department of Andtomy, Mail Stop 408, Hahnemann University, Broad & Vine, Philadelphia, Pennsylvania 19102. Please read notice to contributors on inside back cover page for preparation instructions. Officers o f the American Association of Anatomists for 1989-90: Jerome Sutin, president; Roger R. Markwald, president emeritus; Karen Hitchcock, president-elect; Jennifer H. LaVail, first vicepresident; Donald A. Fischman, second vice-president; Charles E. Slonecker, program secretary; Marilyn Zimny, program secretaryelect; Robert D. Yates, secretary-treasurer. Authorization to photocopy items for internal or personal use, o r the internal or personal use of specific clients, is granted by Alan R. 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