Fourteen years have passed since the publication of David Spencer Smith's Insect Cells: Their Structure and Function. Here the results of a decade of electronmicroscopic studies on insect cells were summarized in an organized and integrated fashion for the first time, and the ultrastructural characteristics of different specialized cells and tissues were abundantly illustrated in the 117 plates this monograph contained. In the intervening period great progress has been made in the field of Insect Ultrastructure. Organelles not even mentioned in Smith's book, such as synaptonemal complexes, clathrin baskets, fusomes, and retinular junc tions, have been identified and functions proposed for them. There have also been many technical advances that have profoundly influenced the direction of subsequent research. A spectacular example would be the development by Miller and Beatty of the chromosomal spreading technique which allowed for the first time ultrastructural studies on segments of chromosomes containing genes in various stages of replication and transcription. Then there is the freeze-fracture procedure first described by Moor and his colleagues. This technique permitted an analysis of intercellular junctions that was impossible with the conventional sectioning methods. The results greatly clarified our understanding of the channels for ion movement and the permeability barriers between cells and also the membrane changes that occur during the embryonic differentiation and metamorphosis of various types of insect cells."

How organisms come to possess adaptive traits is a fundamental question for evolutionary biology. Although it is almost impossible to demonstrate evolution in the laboratory, this issue can be approached by using an unusual organism, Dark-fly: "Drosophila melanogaster" kept in complete darkness for 57 years through 1,400 generations, which corresponds to 28,000 years in terms of human generations. Has Dark-fly adapted to an environment of total darkness? If so, what is the molecular nature of the adaptation? In "Evolution in the Dark," the remarkable findings from the Dark-fly project performed at Kyoto University are presented. It was found that Dark-fly did not have poor eyesight, but rather exhibited higher phototaxis ability and displayed lengthened bristles on the head that function as tactile receptors. Circadian rhythms were weakened but still retained in Dark-fly. With recent progress in genome science enabling researchers to perform whole genome sequencing for Dark-fly, a large number of mutations were identified including genes encoding a light receptor, olfactory receptors, and enzymes involved in neural development. The Dark-fly project is a simple but very long-term experiment. Combined with advanced techniques in genetics and genomics, it is a valuable tool for understanding the molecular nature of adaptive evolution."

Molecular biology emerged from advances in biochemistry during the 1940s and 1950s, when the structure of the nucleic acids and proteins were elucidated. Beginning in the 1970s, with nucleic acid enzymology and the discovery of the restriction enzymes, the tools of molecular biology became widely available and applied in cell biology to study how genes are regulated. This new knowledge impacted endocrinology and reproductive biology since it was largely known that the secretion of the internal glands affected the phenotypes, and expression of genes. Modern reproductive biology encompasses every level of biological study from genomics to ecology, encompassing cell biology, biochemistry, endocrinology and general physiology. All of these disciplines require a basic knowledge, both as a tool and as an essential aid to a fundamental understanding of the principles of life in health and disease. Overall, molecular biology is central to scientific studies in all living matter, impacting disciplines such as medicine, related health sciences, veterinary, agriculture and environmental sciences. In this book, the basic biochemistry of nucleic acids and proteins are reviewed. Methodologies used to study signaling and gene regulation in the endocrine/reproductive system are also discussed. Topics include mechanisms of hormone action and several endocrine disorders affecting the reproductive system. Professionals in the medical, veterinary and animal sciences fields will find exciting and stimulating material enhancing the breadth and quality of their research.

This series was established to create comprehensive treatises on specific topics in developmental biology. Such volumes serve a useful role in developmental biology, since it is a very diverse field that receives contributions from a wide variety of disciplines. This series is a meeting-ground for the various practi tioners of this science, facilitating an integration of heterogeneous information on specific topics. Each volume is intended to provide the conceptual basis for a comprehen sive understanding of its topic as well as an analysis of the key experiments upon which that understanding is based. The specialist in any aspect of devel opmental biology should understand the experimental background of the field and be able to place that body of information in context to ascertain where additional research would be fruitful. At that point, the creative process gener ates new experiments. This series is intended to be a vital link in that ongoing process of learning and discovery."

... an adult poet is simply an individual in a state of arrested development-in brief, a sort of moron. Just as all of us, in utero, pass through a stage in which we are tadpoles, ... so all of us pass through a state, in our nonage, when we are poets. A youth of seventeen who is not a poet is simply a donkey: his development has been arrested even anterior to that of the tadpole. But a man of fifty who still writes poetry is either an unfortunate who has never developed, intellectually, beyond his teens, or a conscious buffoon who pretends to be something he isn't-something far younger and juicier than he actually is. -H. 1. Mencken, High and Ghostly Matters, Prejudices: Fourth Series (1924) Where would evolution be, Without this thing, heterochrony? -M. L. McKinney (1987) One of the joys of working in a renascent field is that it is actually possible to keep up with the literature. So it is with mixed emotions that we heterochronists (even larval forms like myself) view the recent "veritable explosion of interest in heterochrony" (in Gould's words in this volume). On the positive side, it is ob viously necessary and desirable to extend and expand the inquiry; but one regrets that already we are beginning to talk past, lose track of, and even ignore each other as we carve out individual interests."

Recent progress in recombinant DNA technology and the availability of a number of nonpeptide subtype-specific receptor antagonists and of specific antibodies to components of prorenin-renin-angiotensin system (PRAS) have led to rapid advances in the under standing of the multifaceted role of angiotensin II, classically known as a peptide hormone of cardiovascular homeostasis. Accumulating evidence sug responsible for the regulation gests that, in addition to its role in salt and water metabolism, PRAS may control other physiological functions including neurosecretion, cellular proliferation, hypertrophy and/or differentiation, angiogenesis and gonadal function. At the same time, it is becoming evident that the specialized functions of endocrine glands are not only regulated by trophic hormones but also by locally produced paracrine/autocrine factors. The concept is emerging that tissue PRAS is one such locally active regulatory system. With more and more reproductive and endocrine organs being added to the list of tissues that contain a local tissue PRAS, questions are being raised by the reproductive biologists and endocrinologists as to the role of such systems in the tissues of their interest. On the other hand, the cardiovascular and renovascular physiologists are wondering about the relevance of PRAS in various peripheral tissues compared to those of the classical cardiovascular organs. It appeared, therefore, that the time was ripe for a meeting to consider a merger of interest in these two important but heretofore distinct areas of physiology."

Of the three organizers of this NATO Advanced Research Workshop on "Neocortex: Onto geny and Phylogeny," one derived most of his knowledge about neocortex from studies on birds, another had never studied any animal but the cat and could probably recognize not more than ten animal species, and the third had very limited experience with mountaineering. They had in common the belief that evolutionary thinking permeates what biologists do, but that evolution of species and structures cannot be directly experimentally addressed. Although the fossil record can provide some major insights, the inroad to the evolution of the brain is indirect, via comparative anatomy and developmental biology. By identifying similarities and differences between brain structures in the species at hand, comparative anatomy generates hypotheses of evolutionary transformations. By understanding the rules of morphological transformation, developmental biology can, in principle, estimate the likelihood that a given transformation may have actually occurred. The meeting was a way to check if this notion is viable, by gathering together scientists from these two fields. Standing, left to right: F. Ebner, V. Caviness, M. Weisskopf, B. Fritszch, N. Swindale, J. Walter, H. Karten, J. Pettigrew, E. Welker, M. Cynader, D. Frost, L. Lopez-Mascaraque, P. Katz, H. Jerison, E. Soriano, Mayor of Alagna, Dr. G. Guglielmina, and associate, H. Van der Loos, B. Finlay, H. Scheich, C. Ruela. Seated: S. Pallas, T. Lohmann, J. De Carlos, F. Valverde, G. Innocenti, M. Diamond v "Gathering" does not accurately describe what really happened."

Leo Buss expounds a general theory of development through a simple hierarchical extension of the synthetic theory of evolution. He perceives innovations in development to have evolved in ancestral organisms where the germ line was not closed to genetic variation arising during the course of ontogeny.

Originally published in 1988.

The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These paperback editions preserve the original texts of these important books while presenting them in durable paperback editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.

It is a source of great satisfaction to us that a Second Edition of this handbook should be called for, especially because it has given us the opportunity to produce, we believe, a better book. Eighteen chapters, amounting to one-third of the whole, are new, and of these, 13 deal with subjects not covered at all in the First Edition. We have paid more attention to embryonic and fetal growth, with chapters on cell differentiation (Lehtonen and Saxen), embryonic growth (O'Rahilly and Muller), control offetal size (Snow), regulation offetal growth (D'Ercole and Underwood), and ultrasonic studies offetal growth (Meire). At last the data are available for a chapter on the evolution of the human growth curve, by Eliz- abeth Watts. Large parts of the endocrine section have been rewritten (by Michael Preece, and by William Crowley and Margaret Wierman), and the genetics section has been largely recast, with new contributions by William Mueller and Ronald Wilson. Reynaldo Marto- rell has contributed a new chapter on growth in developing countries, and Tanner discusses growth surveys and standards as well as catch-up growth. Finally, there are two new chap- ters dealing with growth as a monitor of the health of populations-one by Tadeusz Bie- licki, considering the contemporary scene, and the other by Robert Fogel, on the contri- bution that such studies are making to the economic history of the eighteenth and nineteenth centuries.

The past decade has seen a steady increase in studies oflemur behavior and ecology. As a result, there is much novel information on newly studied populations, and even newly discovered species, that has not yet been published or summarized. In fact, lemurs have not been the focus of an international symposium since the Prosimian Biology Conference in London in 1972. Moreover, research on lemurs has reached a new quality by addressing general issues in behavioral ecology and evolutionary biology. Although lemurs provide important comparative information on these topics, this aspect of research on lemurs has not been reviewed and compared with similar studies in other primate radiations. Thus, as did many in the field, we felt that the time was ripe to review and synthesize our knowledge of lemur behavioral ecology. Following an initiative by Gerry Doyle, we organized a symposium at the XIVth Congress of the International Primatological Society in Strasbourg, France, where 15 contributions summarized much new information on lemur social systems and their ecological basis. This volume provides a collection of the papers presented at the Strasbourg symposium (plus two reports from recently completed field projects). Each chapter was peer-reviewed, typically by one "lemurologist" and one other biologist. The first three chapters present novel information from the first long-term field studies of three enigmatic species. Sterling describes the social organization of Daubentonia madagascariensis, showing that aye-aye ranging patterns deviate from those of all other nocturnal primates.

Tissue engineering is a new field of biomedical engineering, in which synthetic materials are used together with biological components such as tissue fragments, cells, proteins to encourage tissue regeneration, regrowth, and repair. This book introduces the principles of tissue engineering in a unique way that is ideally suited for the modern engineering student. A review of developmental biology is presented early in the book, since biological development is the fundamental process of most relevance for tissue engineering. The study of development provides a pathway to basic bioengineering units on cell adhesion, migration, assembly, and transport, which are integrated in the final sections of the book into tissue engineering processes (such as cell delivery, growth factor administration, and polymeric scaffold materials).

Gastrulation is a fundamental process of early embryonic development. It involves virtually every aspect of cell and developmental biology and results in the formation of fundamental structural elements around which a developing animal's body plan is organized. As such it is not only an important process, but also one that is complicated and not easily dissected into its component parts. To understand the mechanisms of gastrulation one must acknowledge that gastrulation is fundamentally a biomechanical process (that is, a problem of cells generating forces in a three dimensional array, patterned in space and time such that appropriate tissue movements are executed). Three intertwined questions emerge: what cell activities generate forces, how are these cell activities patterned in space and time, and how are the resulting forces harnessed in three dimensional domains? To address these issues it is important to define and characterize regional cell behaviors and to learn how they are patterned in the egg and/ or by subsequent cell and tissue interactions. At the biochemical level, what are the cellular and extracellular molecules that control cell behavior? Finally, how are specific patterns of cellular activity integrated to produce tissue behavior? The task of answering the above questions, an immense task in itself, is compounded by the fact that the morphogenetic movements of gastrulation and their underlying mechanisms vary between different organisms.

The present monograph is the fourth of six volumes which review the Hypotricha, a major group of the spirotrichs. The book is about the Gonostomatidae, the Kahliellidae, and some taxa of unknown position in the hypotrichs. Gonostomum was previously misclassified in the Oxytrichidae because its type species Gonostomum affine has basically an 18-cirri pattern, which is dominant in the oxytrichids. A new hypothesis, considering also molecular data, postulates that this 18-cirri pattern evolved in the last common ancestor of the hypotrichs and therefore it appears throughout the Hypotricha tree. The simple dorsal kinety pattern, composed of only three bipolar dorsal kineties, and gene sequence analyses strongly suggest that Gonostomum branches off rather early in the phylogenetic tree. Thus, the Gonostomatidae, previously synonymised with the oxytrichids, are reactivated to include the name-bearing type genus and other genera (e.g., Paragonostomum, Wallackia, Cladotricha) which have the characteristic gonostomatid oral apparatus. The Kahliellidae are a rather vague group mainly defined via the preservation of parts of the parental infraciliature. The kahliellids preliminary comprise, besides the name-bearing type genus Kahliella, genera such as Parakahliella and its African pendant Afrokahliella or the monotypic Engelmanniella. In total 68 species distributed in 21 genera and subgenera are revised. As in the previous volumes almost all morphological, morphogenetic, molecular, faunistic, and ecological data, scattered in almost 700 papers, are compiled so that the four volumes (Oxytrichidae, Urostyloidea, Amphisiellidae and Trachelostylidae, Gonostomatidae and Kahliellida) provide a detailed insight into the biology of almost 500 species of hypotrichs. The series is an up-to-date overview about this highly interesting taxon of spirotrichous ciliates mainly addressed to taxonomists, cell biologists, ecologists, molecular biologists, and practitioners.

Defined as, "The science about the development of an embryo from the fertilization of the ovum to the fetus stage," embryology has been a mainstay at universities throughout the world for many years. Throughout the last century, embryology became overshadowed by experimental-based genetics and cell biology, transforming the field into developmental biology, which replaced embryology in Biology departments in many universities. Major contributions in this young century in the fields of molecular biology, biochemistry and genomics were integrated with both embryology and developmental biology to provide an understanding of the molecular portrait of a "development cell." That new integrated approach is known as stem-cell biology; it is an understanding of the embryology and development together at the molecular level using engineering, imaging and cell culture principles, and it is at the heart of this seminal book. Stem Cells and Regenerative Medicine: From Molecular Embryology to Tissue Engineering is completely devoted to the basic developmental, cellular and molecular biological aspects of stem cells as well as their clinical applications in tissue engineering and regenerative medicine. It focuses on the basic biology of embryonic and cancer cells plus their key involvement in self-renewal, muscle repair, epigenetic processes, and therapeutic applications. In addition, it covers other key relevant topics such as nuclear reprogramming induced pluripotency and stem cell culture techniques using novel biomaterials. A thorough introduction to stem-cell biology, this reference is aimed at graduate students, post-docs, and professors as well as executives and scientists in biotech and pharmaceutical companies.

Anatomy, to be sure, is the essential foundation of clinical practice, but it is much more than that. First and foremost, anatomy is a biological science. There is order and logic to the organization of the human body and the arrangement of its parts. And, as all sciences, anatomy offers challenge and discovery. Concepts in Anatomy is not a textbook, but more of a brief handbook that is selective rather than encyclopedic in scope, conception rather than particular in its approach. It stresses general principles, so as to minimize rote learning, and it provides order and direction to the study of gross anatomy. Anatomy is inherently complicated and confusing; this volume helps you make sense of it in a way that also aims to inspire its study. Richly illustrated with original drawings, Concepts in Anatomy is a valuable resource for anyone currently studying or teaching the subject, or as a reference for advanced researchers.

Regeneration, i.e. the replacement of lost body parts by new outgrowths or by remodelling existing tissues, has been studied for centuries. However, in recent years important developments took place in this field too, owing to new soph isticated techniques and to novel theoretical concepts. Advances in Molecular Genetics, Biochemistry, Cell and Neurobiology, Immunology, to mention a few of them, are the main causes of this resurgence of interest in regeneration. As a consequence, more and more meetings and pUblications are devoted, either exclusively or for a large part, to basic and applied research of regenerative processes. "Regeneration ists" scattered in laboratories allover the world and accus tomed to know each other through exchange of reprints - occa sionally an encounter in a large conference - tend now to form small groups, even societies and to institutionalize their meetings. Although the critical mass of scientists involved in regeneration research does not seem yet to be reached, for an autonomous development of this sector, regular and frequent meetings of experts appear useful, even necessary. Such a meeting was convened in Saronis, near Athens, Greece, from 19 to 23 September 1988 and sponsored by the NATO Science Committee and the University of Athens. The present volume contains the contributions to this Advanced Research Workshop on "Recent Trends in Regeneration Research". About 50 biologists from different countries, either mem bers of the Alliance or outside it (U.R.S.S., India, Egypt, Switzerland, Sweden) took part, mostly as invited speakers.

Perinatal problems in thyroid gland physiology are common but complicated and present a diagnostic dilemma for the primary clinician. In December 1990, an international group of basic and clinical investigators gathered in Longboat Key, Florida to address these issues. The participants included internists, obstetricians, pedia tricians, neurologists, pathologists and basic scientists in cellular metabolism, endocrine physiology, and molecular biology. The presentations contained within this book bring together their most current and vital research related to the field of perinatal thyroidology. This book is based on the dynamic and fruitful exchange of the participants at the symposium. We are indebted to these individuals whose valuable insights and efforts are contained within this text. Barry B. Bercu Dorothy I. Shulman vii CONTENTS Session I Mechanism of Thyroid Hormone Action 1 Leslie J. DeGroot Thyroid System Ontogeny in the Sheep: A Model for Precocial Mammalian Species * . . * * 11 Delbert A. Fisher Pathologic Studies of Fetal Thyroid 27 Development * * * * * * * Douglas R. Shanklin Thyroid Hormone Control of Brain and Motor Development: Molecular, Neuroanatomical, 47 and Behavioral Studies * * * * * * * S. A. Stein, P. M. Adams, D. R. Shanklin, G. A. Mihailoff, and M. B. Palnitkar The Thyroidectomized Pregnant Rat: An Animal Model to Study Fetal Effects of Maternal Hypothyroidism 107 Susan P. Porterfield and Chester E.

Chemical Anatomy of the Zebrafish Retina is an excellent reference, providing excellent images and insight into one of the most increasingly important model systems in neurobiology today. Papers include a visually stunning molecular phenotype atlas and an exhaustive treatment of the neurochemical anatomy of the zebrafish retina as determined by immunocytochemistry.

Over the past decade, the AIDS pandemic has propagated so widely and exerted such a dev astating impact that one may properly ask the question, Why not concentrate all AIDS efforts on disease control alone? Why link AIDS with women's reproductive health? What is the scientific basis for this linkage? And how might AID~ control and women's health objectives be promot ed simultaneously? These questions constitute the principal themes addressed in this monograph. The 15 chapters in this volume are intended to provide state-of-the-art reviews of key interac tions between AIDS and women's reproductive health for an audience of scientists and policy makers in the AIDS and population fields. Impetus for this monograph comes in pan from what we perceive to be an inadequate global response, thus far, to AIDS and women's health ;>roblems. A common platform has failed to emerge among the disparate professional communities working in the areas of AIDS, STDs, and family planning. As a result, endeavors in these fields have been isolated, and opportunities for joint action have been missed. An enormous and, as yet, unharnessed potential exists for power ful interdisciplinary collaborations that could strengthen policies and programs against these pressing health problems of humankind.

At present, we do not fully understand at what stage of the evolution of living matter the first traces of defense reactions occurred. We even do not fully understand how and why immune systems reached their contem porary state in advanced vertebrates and man. It may be expected that in the near future these questions will be answered by comparative and develop mental biology. Together with an extraordinary explosion of our knowledge about immunity of mammals including man, an increase in the interests concerning origin and development of immune mechanisms at lower stages of the phylogeny can be observed. The search for simple types of immune mechanisms in less complex but still evolutionary successful animals is promising and may contribute to better understanding of highly complex immune adaptive responses in mammals. It is important to note that comparative and evolutionary immunology differs greatly from other branches of biomedical science. Apart from immunology and molecular biology, a specialist in this discipline has to be familiar with every detail of taxonomy, comparative anatomy, physiology, embryology, and even with the phyletic relationships of animals. Probably no monography could deal with the entire animal kingdom, because, in many cases, the insights into questions about immune mecha nisms of many animal groupings or phyla, and their possible evolutionary implications, are unknown or just now beginning to take shape. For the moment, our knowledge on such matters relies upon reconstructions of ideas that we have deduced from studies on members of relative taxa."

Mesodenn is a key tissue in early development. It is involved in the differentiation of almost every organ in the body, not merely as a structural component, but as an active participant in the establishment of diverse cell types. All mesodenn is derived from ectoderm. Its appearance signals the start of a significant new phase in the development of the embryo. At this time all three genn layers are now present and myriad sequences of cell and tissue interactions begin to occur which will eventually give rise to the entire embryo. The control of the growth and differentiation of the mesoderm is critical for the production of a normal individual. Indeed, disturbance of the patterning of the mesoderm or of its interaction with other tissues plays a critical part in the fonnation of most congenital anomalies. The main focus of this book is therefore on the establishment, divergence and specialisation of mesodermal derivatives. The central role of the mesoderm in development has long been appreciated and a wide literature exists on its activity in certain specialised situations. Recently, however, an impetus to its study has been provided by new approaches opened up through biotechnological advances. Many of these advances are reflected in the reports in this volume. Scientists from various disciplines have become drawn to mesodermal tissues, and this volume may help them find a framework within which their work will fit.

Human reproduction is the most dynamic of processes. The events which lead to the birth of a normal healthy infant have their origin long before actual fertilization. Indeed, the whole process can be looked upon as a continuum. Human fertilization and early development, once sequestered in the protective environment of the fallopian tubes and uterus, have now been exposed in the laboratory. These events have, over time, been extensively observed and catalogued in animal models. The tools of modem morphology and molecular biology have reopened issues long since considered settled as facets of early reproduction are reexplored. This volume, consisting of the proceedings of a workshop on uterine and embryonic factors in early pregnancy, has been designed to enhance that effort. Attention is focused largely on early embryonal development with special attention to the interrelationship between the embryo and the uterus in early pregnancy. Each of the contributing scientists brings with him or her the perspective of one specific discipline or another. The common denominator is the application of emerging techniques in modem molecular biology to problems pertaining to embryonal-uterine interaction. The goal is to consider specific areas of concern in a multidisciplinary way and to reexplore the factors behind early development and implantation. Uterine complement, the function of uterine macrophages immunoregulatory loops in the peri-implantation period, colony stimulating factors and interferon-like factors are reviewed and their interrelationship explored. Uterine angiogenesis factors as well as embryonic growth factors are also considered.

Following pioneering work by Harrison on amphibian limbs in the 1920s and by Saunders (1948) on the apical ridge in chick limbs, limb development became a classical model system for investigating such fundamental developmental issues as tissue interactions and induction, and the control of pattern formation. Earlier international conferences, at Grenoble 1972, Glasgow 1976,and Storrs, Connecticut 1982, reflected the interests and technology of their time. Grenoble was concerned with ectoderm-mesenchyme interaction, but by the time of the Glasgow meeting, the zone of polarizing activity (ZPA) and its role in control of patterning was the dominant theme. Storrs produced the first intimations that the ZPA could be mimicked by retinoic acid (RA), but the diversity of extracellular masrix ~olecules,particularly in skeletogenesis,was the main focus of attention. By 1990, the paradigms had again shifted. Originally, the planners of the ARW saw retinoic acid (as a possible morphogen controlling skeletal patterning), the variety of extracellular matrix components and their roles, and the developmental basis of limb evolution as the leading contemporary topics. However, as planning proceeded, it was clear that the new results emerging from the use of homeobox gene probes (first developed to investigate the genetic control of patterning of Drosophila embryos) to analyse the localised expression of "patterning genes" in limb buds would also be an important theme.

It is nearly a decade since the first Male Mediated Developmental Toxicity conference was held in Pittsburgh. The continuing public/scientific interest, growing amounts of animal data, introduction of innovative technologies, and increasing quantity of human epidemiological studies all suggest that male-mediated developmental toxicity is of major concern. A number of researchers concluded that a Second International Confer- ence on Male Mediated Developmental Toxicity was necessary. The ensuing volume is particularly timely because it impacts on areas of special emphasis in many countries, with respect to children's and reproductive health, as well as to basic molecular mecha- nisms of environmental insult, and genetic susceptibility and predisposition. The Programme and Local Organizing Committee, composed of Barbara Hales (Chair, McGill University), BernardRobaire (McGill University), Daniel G. Cyr (INRS/ Armand Frappier), Jacquetta M. Trasler (McGill University), Andrew F. Olshan (Uni- versity of North Carolina), Sally Perreault Damey (US EPA), Donald R. Mattison (March of Dimes), and Jan M. Friedman (University of British Columbia), spent over two years identifying individuals who had made key contributions in this field over the past decade and planning various aspects of the meeting. The meeting was held in Montreal in June 2001. A total of 132 persons, coming from five continents and representing some 18countries, took an active role in the proceedings. The conference was considered by all attendees to be a rousing success. Important discussions were held in the four break-out sessions, with a preliminary set of recommendations for action being presented by each panel.

This volume reports the proceedings of a NATO Advanced Workshop held in Castelvecchio Pas coli, Italy, from August 28 - September 1, 1989. An important inspiration for this Workshop came from our studies in Helsinki and Denmark, which have found that exposure to an influenza epidemic during the second trimester of fetal development increases the risk of adult schizophrenia. This finding has stimulated an important new hypothesis in the study of the etiology of schizophrenia. It has suggested the possiblity that disturbances of brain development during gestation may contribute to the risk of adult schizophrenia. We determined that it would be of value to bring together schizophrenia researchers and those doing basic studies of the development of the brain. Both groups of researchers were encouraged to communicate at a level that would help other scientists to integrate their knowledge and techniques into their own discipline. For this reason, perhaps, the papers of this volume are remarkably clear and not difficult to understand. The first four chapters describe the neurochemical and structural aspects of brain development. The chapter by Dziegielewska and Saunders discusses transport mechanisms and the properties of endogenous and exogenous substances that control the internal environment of the developing brain. In the second chapter, Nowakowski reports on his studies of the develop ment of the hippocampus in mice genetically inbred to exhibit disruptions of neural migration.