Constructional morphology explains features of organisms from a constructional and functional point of view. By means of physical analysis it explains the operational aspects of organic structures - how they can perform the activities organisms are expected to fulfil in order to survive in their environment. Constructional morphology also explains options and constraints during the evolution determined by internal constructional needs, ontogenetic demands, inherited organizational preconditions and environmental clues.

In view of the increasing problems of waste disposal in the Netherlands, plans were made to pipeline the waste to the Ems-Dollard estuary. To evaluate the practicability a project was started with the aim to implement a simulation model of an estuary ecosystem. This model was based on the knowledge of the hydrology, geochemistry and biology of the Ems estuary. For this approach data of the abiotic and biotic environment were collected in studies of the Ems estuary and are presented in this report. With its comprehensive information of biological processes as food webs, biomass production and nutrient supply, as well as of sedimentological and flux parameters, this book can be considered as a general model of an estuary ecosystem.

The eye has fascinated scientists from the earliest days of biological in vestigation. The diversity of its parts and the precision of their interaction make it a favorite model system for a variety of developmental studies. The eye is a particularly valuable experimental system not only because its tissues provide examples of fundamental processes, but also because it is a prominent and easily accessible structure at very early embryonic ages. In order to provide an open forum for investigators working on all aspects of ocular development, a series of symposia on ocular and visual devel opment was initiated in 1973. A major objective of the symposia has been to foster communication between the basic research worker and the clinical community. It is our feeling that much can be learned on both sides from this interaction. The idea for an informal meeting allowing maximum ex change of ideas originated with Dr. Leon Candeub, who supplied the nec essary driving force that made the series a reality. Each symposium has concentrated on a different aspect of ocular development. Speakers have been selected to approach related topics from different perspectives."

Following the first Conference in Florida, U.S.A. (1970) and the second in Krakow, Poland (1975), the Third International Conference on Ephemeroptera was held in Hinnipeg, Manitoba, Canada from the fourth to the tenth of July, 1979, at the invitation of the Inter- national Permanent Comraittee on Ephemeroptera. (H.L. Peters, U.S.A. (Chairman); I. Uu11er-Liebenau, \Jest Germany; H.J. Schoonbee, South Africa; G.F. Edmunds, Jr., U.S.A.; E.F. Riek, Australia; R. Sowa, Poland). The Conference \-laS hosted by the Freshwater Institute (Department of Fisheries and Oceans, Canada) and the University of Hanitoba and sponsored by the International Union of Biological Science. Sixty delegates from 11 countries attended. Registration for the Conference took place on July 4th, and in the evening the delegates got acquainted, or renewed old acquain- tances, at an informal gathering in the Hospitality Room at Hary Speech1y Hall, the University residence which accomodated most of the delegates. Next morning, in the Fletcher-Argue theatre, the Conference was opened by the Honorary Chairman, Dr. F.P. Ide, who welcomed the delegates, then introduced the guest speakers: G.H. Lawler, Director-General of the Hestern Region of the Canada Depart- ment of Fisheries and Oceans; P. Jarvis, Deputy Hinister, aanitoba Department of lUnes, Natural Resources and Environment, and D. R.

Described here are the origin and general trends in the development of fishing from the earliest times up to the present in various parts of the world. The techniques applied and the economic and social problems involved are covered. Fishing methods have not changed much since the Stone Age, but continuous technical improvements like the construction of sea-worthy ships, more efficient gear, and finally mechanization of fishing have led to enormous development and a high fish production, of now 100 million tons per year. Extensive utilization has caused heavy overexploitation of the resources and consequently growing concern. The book concludes with an evaluation of perspectives for the future utilization of living resources.

The structural and chemical limitations to respiratory gas exchange existing between the ambient medium and the cell are comprehensively treated. Beginning with an examination of the natural oscillations of respiratory gases in both terrestrial and aquatic environments, Vertebrate Gas Exchange details the structures involved in convecting the medium (air or water), the morphometrics of capillary gas transfers, and gas transfer kinetics. Important features include details on measurement techniques associated with tissue capillary supply and gas exchange kinetics.

ADVANCES IN COMPARATIVE AND ENVIRONMENTAL PHYSIOLOGY helps biologists, physiologists, and biochemists keep track of the extensive literature in thefield. Providing comprehensive, integrated reviews and sound, critical, and provocative summaries, this series is a must for all active researchers in environmental and comparative physiology. The present volume contains six reviews on: - Motile Activities of Fish Chromatophores. - Epithelial Transport of Heavy Metals. - Heavy Metal Cytotoxicity in Marine Organisms. - Comparative Pulmonary Morphology and Morphometry. - Molecular Adaptations in Resistance to Penicillins. - Molecular Adaptations of Enzymes From Thermophilic and Psychrophilic Organisms.

Being both broad - perception and motor organization - and narrow - just onegroup of animals - at the same time, this book presents a new unified framework for understanding perceptuomotor organization, stressing the importance of an ecological perspective. Section I reviews recent research on a variety of sensory and perceptual processes in birds, which all involve subtle analyses of the relationships between species' perceptual mechanisms and their ecology and behaviour. Section II describes the variousresearch approaches - behavioural, neurophysiological, anatomical and comparative - all dealing with the common problem of understanding how the activities of large numbers of muscles are coordinated to generate adaptive behaviour. Section III is concerned with a range of approaches to analyzing the links between perceptual and motor processes, through cybernetic modelling, neurophysiological analysis, and behavioural methods.

Genetic constraints on adaptive evolution can be understood as those genetic aspects that prevent or reduce the potential for natural selection to result in the most direct ascent of the mean phenotype to an optimum. The contributions to this volume emphasize how genetic aspects in the transmission of traits constrain adaptive evolution. Approaches span from quantitative, population, ecological to molecular genetics. Much attention is devoted to genetic correlations, to the maintenance of quantitative genetic variation, and to the intimate relation between genetics, ecology, and evolution. This volume addresses all evolutionary biologists and explains why they should be wary of evolutionary concepts that base arguments purely on phenotypic characteristics.

It is widely recognized that spiral grain in trees severely reduces the value of sawn timber through warping and loss of strength, and that it also causes problems for other wood uses as diverse as transmission poles or plywood. Yet, paradoxically, there are highly valued grain patterns including wavy and interlocked grain, whose origins in the cambium invite direct comparison with those of spiral grain, so that many authorities believe them to be related phenomena. In recent years this concept has prompted extensive research into the anatomy, genetics, and physiology of all such grain patterns in wood. As a result it has become apparent that tree cambia provide excellent systems through which to study the origins of stem polarity and the complex processes of morphogenetic control in plants. Beside these and other pressing topics for research, the book examines methods of measuring grain deviations, and considers their influence on wood properties, on the economics of timber production, and on wood manufacturing.

A considerable amount of information on the retinal morphology in fishes has been accumulating during the past century. Among the vertebrates, fishes are a highly successful group, both in number of species and in the adaptive radiation of forms. For instance, 415 teleost families are now recognised (GREENWOOD, ROSEN, WEITZMANN and MYERS, 1966), and the 20,000 odd fish species mentioned in text-books have been by far out numbered. The fish retina also shows considerable variations, in conformity with the extreme morphological diversification reached by piscine forms, in colonising all conceivable aquatic habitats and developing a wide spectrum of life habits. We intend to illustrate this in the present Atlas, a collection of short texts and photomicrographs of the retina from about one hundred fish families. This Atlas is intended also to fulfil other purposes. One of them is to present in a phylogenetic order the rather scattered data on fish retinal structure, with appropriate illustrative material; another is to assist the visual physiologist or biochemist in his search for a retina with particular morpholog ical features compatible with his specific requirements. In other words, what we aim at is a ready pool of information for laymen, students, and specialists of varied interests. The material used for this Atlas comes from various sources."

Human activities are causing species extinctions at a rate and magnitude rivaling those of past geologic extinction events.
Exploring mediterranean-type ecosystems - the Mediterranean Basin, California, Chile, Australia, and South Africa - this volume addresses the question whether biological diversity plays a significant role in the functioning of natural ecosystems, and to what extent that diversity can be reduced without causing system malfunction. Comparative studies in ecosystems that are similar in certain respects, but differ in others, offer considerable scope for gaining new insights into the links between biodiversity and ecosystem functioning.

Sympathetic afferent fibers originate from a visceral organ, course in the thoracolumbar rami communicantes, have cell bodies located in dorsal root ganglia, and terminate in the gray matter of the spinal cord. Sympathetic afferent fibers from the heart transmit information about noxious stimuli associated with myocardial ischemia, i. e. angina pectoris. Previous reviews have described the characteristics of cardiovascular sympathetic afferent fibers (Bishop et al. 1983; Malliani 1982). This review summarizes that work and focuses on the neural mechanisms underlying the complexities of angina pectoris. In order to understand anginal pain, cells forming the classical pain pathway, the spinothalamic tract (STn, were chosen for study. These cells were chosen to address questions about anginal pain because they transmit nociceptive informa of pain. Antidromic tion to brain regions that are involved in the perception activation of STT cells provided a means of identifying cells involved with trans mission of nociceptive information in anesthetized animals. Other ascending pathways may also transmit nociceptive information, but many studies show that the STT plays an important role. Visceral pain is commonly referred to overlying somatic structures. The pain of angina pectoris can be sensed over a wide area of the thorax: in the retrosternal, precordial anterior thoracic, and anterior cervical regions of the chest; in the left or sometimes even the right shoulder, arm, wrist, or hand; or in the jaw and teeth (Harrison and Reeves 1968)."

with the issues involved in the management of salmon fishing. farming and ranching and the implications for production costs and the availa bility of supplies. Chapters 6 and 7 investigate processing. marketing and distribution and Chapter 8 discusses the workings of salmon markets and the main factors affecting the demand for salmon. Finally. chapter 9 summarises the main findings of the study and considers the issues likely to define the future of the industry. The main interest of the book is in salmon sold commer cially and mention is only made in passing of the rather different. though important. issues involved in the management of sport or recreation fisheries. This book does not cover all species of salmon but concentrates on the main species of current commercial significance. These are the five commercially important species of Pacific salmon all of which belong to the single separate genus ONCORHYNCHUS together with SALMO SALAR. the Atlantic salmon. The related SALMO GAIRDNERI (rainbow trout) and SALMO TRUTTA (brown troutl seatrout) are outside the scope of the book. although since these compete closely with salmon. the relationship is discussed. 1.2 THE SALMON: LIFE CYCLE AND SPECIES The family salmonidae is indigenous to the Northern Hemisphere and is found from the temperate zone northwards to beyond the Arctic Circle. 1n both Pacific and Atlantic waters. They are not. native to the Southern Hemisphere but have been successfully introduced into New Zealand. into Argentina. Venezuela and more recently Chile and the Kerguelen Islands."

"Mr. Wolkenstein's Physical Approaches to Biological Evolution, whether or not it proves to give the ultimate truth on the matters with which it deals, certainly deserves, by its breadth and scope and profundity, to be considered an impor tant event in the philosophical world." This is a quotation from an introduction written by Bertrand Russell for Ludwig Wittgenstein's Tractatus Logico-Philosophicus. I exchanged only name and subject. As for the rest, I could continue quoting Russell, but I would rather say something myself. As Wittgenstein did with formal logic, Wolkenstein rectifies our views on how to approach the logic of life from a formal theoretical basis. Many bio logists do not believe that their subject lends itself to the scrutiny of physical theory. They certainly admit that one can simulate biological phenomena by models that can be expressed in a mathematical form. However, they do not believe that biology can be given a theoretical foundation that is defined within the general framework of physics. Rather, they insist on a holistic approach, banning any reduction to fundamental principles subject to physical theory."

Taxonomy is fundamental to understanding the variety of life forms, and exciting expansions in molecular biology are re- volutionising the obtained data. This volume reviews the ma- jor molecular biological techniques that are applied in ta- xonomy. The chapters are arranged in three main sections:1) Overviews of important topics in molecular taxonomy; 2) Case studies of the successful application of molecular methods to taxonomic and evolutionary questions; 3) Protocols for a range of generally applicable methods. The described techni- ques include DNA-DNA hybridization, DNA fingerprinting, RFLP analysis, and PCR sequencing.

Various kinds of mineralization have been found in many biological systems. Investigations made at a microscopical level using various sophisticated analytical methods and using principles developed in different fields have clarified their mechanisms very much. Sometimes, very similar phenomena have been found in the mineralized tissues of completely different biological systems. Compilation and comparative investigations of such findings obtained from the many specimens systematically collected contribute a great deal to an understanding of the crucial mechanisms and significance of biominerali zation which originated in very primitive organisms and remain in advanced ones. Previously, the functional significance of mineralized tissues was considered mainly from an anatomical point of view based upon their morphological and structural features. However, the recent advance of investigations has made it possible to interpret the func tional significance of biomineralization not only from local and mechanical points of view, but also from a systemic and phylogenetic point of view. It is also well-known that biomineralization has contributed in various ways to geological and oceanographical conditions of the environment in which the organisms were living. During this process, the mechanisms of biomineralization may have evolved to maintain harmony between organisms and their environments."

Adaptation to altitude hypoxia is characterized by a variety offunctional changes which collectively facilitate oxygen trans port from the ambient medium to the cells of the body. All of these changes can be seen at one time or another in the course of hypoxic exposure. Yet, as already stressed (Hannon and Vogel, 1977), an examination of the literature gives only a sketchy and often conflicting picture of the exact nature of these changes and how they interact as a function of exposure duration. This is partly because of the limited number of variables explored in a given study, but it is also attributable to differences in experimental design, differences among species in susceptibility to hypoxia, nonstandardized experimental conditions, lack of proper control of physical (e. g. , temperature) and physiological variables (e. g. , body mass), failure to take measurements at key periods of exposure, and gaps in knowledge about some fundamental mechanisms. Furthermore the available data on animals native to high altitude are meager and/or inconclusive. Extensive further work under well-controlled experimental conditions is required before a detailed picture can be made. Nevertheless, it has been a guiding principle in the prepara tion of this monograph rather to summarize the vastly dis persed material that constitutes the comparative physiology of adaptation to high altitude into a coherent picture, than to provide a comprehensive survey of the field.

Biology of Antarctic Fish presents the most recent findings on the biology of fish in the unique environment of the Antarctic ocean. At present the year-round temperature of the coastal waters is very near -1,87 Degrees C, the equilibrium temperature of the ice-seawater mixture. This extremely low temperature affects different levels of organization of fish life: individuals, organ systems, cells, organelles, membranes, and molecules. Exploring ecology, evolution, and life history as well as physiology, biochemistry, and molecular biology of Antarctic fish the book describes the mechanisms of cold adaptation at all these levels. It provides material for discussion also for fundamental questions in the field of adaptation to an extreme environment and therefore is of particular interest not only to specialized scientists, but also to those involved in basic and evolutionary biology.

Deals with biotechnological approaches incorporated into po- tato improvement progammes. These methods have far-reaching implications for the synthesis of improved, disease- resist- ant and nutritious cultivars of potato.

The picture on the following page is being reproduced here, at the request of the partici pants in the Advanced Research Workshop "Amino Acid Availability and Brain Function in Health and Disease." I displayed this limewood carving, entitled "Neurochemistry," during my closing remarks to this extraordinarily stimulating and productive workshop so ably organized by my collaborator Dr. Gerald Huether. We scientists need two sturdy legs to carry us through all the twists and turns of our academic careers. We should also have, as it were, a reserve leg handy, to help us stay upright when this career ends. My "third leg" is wood carving. The idea for "Neurochemis try" came to me in the plane carrying me to the congress of the International Neuro chemical Society in Jerusalem. We need the hands for our meticulous experimental work, and at least one ear to listen to the messages our neurons send us. A few years ago it would have been premature to hold a workshop on this subject. Now, however, the time was just right to allow an overview of the status of current re search, and to point out the promising new openings it has created. There is no doubt that the book to be published as a result of this workshop will be, for the next years at least, the standard text on the subject. Hearty thanks to all speakers for their brilliant con tributions and to all participants for the lively, uninhibited and stimulating discussion."

Evolution of Castes in Insects l BERNHARD RENSCH The evolution of organisms in the succession of generations has been primarilly achieved through the appearance of new hereditary variants with minor deviations along with the development of stable structures and functions. Harmful mutants were eradicated either immediately or in the subsequent generations through the process of natural selection while unharmful or advantageous ones usually survived. As this process continued, many new races and species developed which possessed structures and functions of a rational nature and which became increasingly independent from their environment. These evolutionary tendencies were also promoted through either geographical, ecological, physiological or genetical isolation of populations. In some phylogenetic lines, there occurred an increase in the number of cells due to additional cellular divisions in the morphogenesis of structures. This opened up the possibility for the development of the division of labour within cellular groups leading to more complicated and consequently more successful functions of tissues and organs. A further advancement in the adaptation of a species to its environment was made possible through specialization for certain functions of whole individuals or groups of individuals.

Based on papers presented at the International Symposium on Sexual Reproduction in Higher Plants, this volume covers the topics: micro- and macrosporogenesis, the activation and recognition of mature pollen, pollen germination and tube emission in vivo and in vitro, pollen and pollen tube cytoskeleton, stigma and style morphology, pollen/stigma interactions, incompatibility mechanisms and gene expression. The reinvestigation of classical topics using modern methods such as immunofluorescence, micromanipulation, freeze-substitution, electron microscopy, etc., is the common basis of all results presented. Especially applied aspects of sexual reproduction important e.g. for crop improvement, are discussed in detail.

Advances in Comparative and Environmental Physiology helps biologists, physiologists, and biochemists keep track of the extensive literature in the field. Providing comprehensive, integrated reviews and sound, critical, and provocative summaries, this series is a "must" for all active researchers in environmental and comparative physiology.