In September 1989, a meeting was held at Needham Hall, The University of Manchester, England, entitled ‘Physical Influences on Embryonic Development in Birds and Reptiles’. The philosophy behind this meeting was to bring together scientists who specialised in the incubation and physiology of avian embryos with those workers interested in reptilian eggs and embryos. Leading authorities within many fields of incubation, oology and embryology were invited to give a presentation reviewing current knowledge within their sphere of research. The idea was to stimulate interest and collaboration between avian and reptilian researchers who may not have had any significant contact previously and to systematically compare and contrast events in birds and reptiles: a task never before attempted due in part to the paucity of reptilian data until the rapid expansion in knowledge of the past five years. Each speaker was also requested to produce a written review which forms the basis of this volume. This book is not a set of conference proceedings. Rather, it aims to be a comprehensive review of relevant reptilian and avian embryonic data: a text designed as a reference guide for the next few years.

The book aims to review incubation and embryology in birds and different kinds of reptiles and covers three major areas: the first deals with the chemical components and structure of eggs; the second examines the effects of the four main determinants of incubation, temperature, water relations, respiratory gas exchange and turning, upon embryonic development together with reviews of the evolutionary significance of incubation parameters.

Conditional (if-then) sentences have long been of central concern in the study of reasoning. Because modern academic practice has compartmentalized three distinct disciplines: linguistics, psychology and philosophy, a tremendous variety of different questions and angles of approach have developed, often independently, and without a common focus. The purposes of this book are: (i) to emphasize the intrinsic connections between the issues that have been addressed within the three disciplines; (ii) to show that all share similar concerns with how human beings use conditional constructions in their language to reason and to communicate their thoughts; and (iii) to point to new directions and potential areas of cross-fertilization for future studies.

The papers are arranged as follows. Part I presents a broad survey of conditionals, the ways in which they are used to reason, and the ways in which they are structured in language (the overview by the editors, and papers by Barwise, Johnson-Laird, and Comrie from the points of view of philosophy, psychology, and linguistics, respectively). Part II presents approaches to particular aspects of conditionals, starting with papers in the tradition of philosophy and formal syntax and semantics that show how the study of conditionals can lead to the refinement of syntactic and semantic theories (Reinhart, ter Meulen, and Veltman). It moves on to papers that focus on the intentions of speakers in using and understanding conditionals from the different perspectives of philosophy, linguistics and psychology (Adams, Van der Auwera, and Fillenbaum).