Contents: Part I:Categories and Concepts in Birds.T.R. Zentall, P. Jackson-Smith, J.A. Jagielo, Categorical Color and Shape Coding by Pigeons. R. Pisacreta, Rudimentary Rule-Governed Behavior in the Pigeon. C.M. Lombardi, J.D. Delius, Size Invariance in Visual Pattern Recognition by Pigeons. J. Emmerton, Pigeons' Perception of Complex Movement Patterns. C.M.E. Ryan, S.E.G. Lea, Pattern Recognition, Updating and Filial Imprinting in the Domestic Chicken. K.M. Steele, Configural Processes in Pigeon Perception. Part II:Shape and Form.D.S. Blough, Form Similarity and Categorization in Pigeon Visual Search. J. Cerella, Shape Constancy in the Pigeon: The Perspective Transformation Decomposed. S.E.G. Lea, C.M.E. Ryan, Unnatural Concepts and the Theory of Concept Discrimination in Birds. R.G. Cook, A.A. Wright, D.F. Kendrick, Visual Categorization by Pigeons. R.J. Herrnstein, Levels of Stimulus Control: A Functional Approach.
