This collection of papers is presented to Sir JOHN ECCLES by his former and present collaborators to commemorate the award of the 1963 Nobel Prize in Medicine, which was shared with A. L. HODGKIN and A. F. HUXLEY. Sir JOHN'S interest in, and influence on, the study of physiology, particularly that of the nervous system, is reflected by the range of topics discussed, and by the distri­ bution of the various authors in laboratories throughout the world. Those who have been privileged to work with him in Oxford, Sydney, Dunedin or Canberra have enjoyed a good discipline in scientific thought, as well as in the use of neurophysiological techniques. Basic knowledge is always transferable, and the inspiration which comes from association with a great scientist is not confined to anyone field of physiology. The contributors to this volume were requested to review briefly that aspect of physiology of current interest to them, and it is hoped that the resulting papers will serve as an up to date review of many physiological problems. The editors are greatly indebted to the publishers, Springer-Verlag, particu­ larly to Dr. H. GOTZE for his advice and interest. It is also a pleasure to thank Mrs. H. WALSH for her unfailing assistance during the preparation of this book. Canberra Melbourne 1965. III CONTENTS Rhythmic thalamic activity. P. Andersen.

Rhythmic thalamic activity.- Differences in the diameter and conduction velocity of motor and fusimotor fibres in nerves to different muscles in the hind limb of the cat.- Some factors governing sensory convergence in the cat's motor cortex.- Control of the neurones of the supraoptic and paraventricular nuclei.- Mammalian slow and fast skeletal muscle.- Some methods of reducing interference caused by stimulus artifacts.- The actions of amino acids upon mammalian neurones.- An example of sensory integration of the stretch reflex.- Viscerotomes and dermatomes: some comparisons of the inner and outer surfaces of the body.- External action currents at cut nerve end.- Interneurones activated by higher threshold group I muscle afferents.- Electrical impedance of striated muscle and its relation to contraction.- Interpretation of the central excitatory and inhibitory states.- The cholinergic factor in the maintenance of experimental atrial fibrillation.- The origin and significance of antidromic activity in motor nerves.- The peripheral mechanisms of cutaneous sensation.- The origin of cerebellar inhibition on Deiters' and intracerebellar nuclei.- Diffusion from constrictions.- The quantal release of transmitter substances.- Membrane calcium and bioelectric potentials.- Transmitter liberation and mobilization in degenerating central synaptic endings.- Post-activation changes in the salivary glands of the dog.- Cholinergic innervation of the cerebral cortex.- An approach to the study of neuroglia and of extracellular space based on recent work on the nervous system of the leech.- Central connections of the sensory paths from the cat's tongue.- Slow synaptic responses in autonomic ganglia.- Physiological observations in foetal transfusion.- Cholinergy and adrenergy in the neural control of sweat glands.- Effects of barbiturates and lack of oxygen on the monosynaptic reflex pathway of the cat spinal cord.- Monoamines and spinal reflexes.- Water metabolism of desert ruminants.- Some applications of input-output technique.- Intracellular recording from neurones of the reticular formation.- Pharmacological stimulation of the deep regions of the human brain by intraventricular injections.- The neurosecretory cells of the mammalian neurohypophysis.- Proprioceptive and exteroceptive projections to the pericruciate cortex of the cat.- The sodium pump of mammalian nerve cells.- Comparison of tendon and bone repair.- Dendritic synaptic patterns: experiments with a mathematical model.- The effect of drugs on the reflex paths to primary afferent fibres.- The role of segmental reflex mechanisms in the regulation of breathing.- Implications of central projections of C fibers in sensory perception.- Some aspects of cerebellar pharmacology.- Specificity in regeneration of optic and olfactory pathways in teleost fish.- The origin of learning. A hypothesis.