THE DIMENSION OFS FISH GILL ISN RELATION （维OFS鱼鳃是关系）.pdf

J. Exp. Biol. (1966), 45, 177-195 17 7 With 4 text-figures Printed in Great Britain THE DIMENSIONS OF FISH GILLS IN RELATION TO THEIR FUNCTION BY G. M . HUGHE S Department of Zoology, University of Bristol (Received 5 March 1966) INTRODUCTION It is known from the extensive measurements of Gray (1954) that the gills of marine fishes of the Atlantic Coast of North America show a wide variation in the extent of their gill area. This is true whether the area is based on the unit of body surface area or on a unit of body weight. Little data are available, however, for fishes from European waters (Byczkowska-Smyk,* 1957, 1958, 1959)- The present investigation was under- taken because earlier work (Hughes Shelton, 1958) suggested that the nature of the gill resistance is an important variable in the ventilating mechanism. Therefore, as part of a comparative study of the respiratory mechanism c . marine fishes (Hughes, 1960) the opportunity was taken to make certain measurements of the gills which might give some indication of the variations in gill resistance of the species studied. From these measurements it was also possible to calculate the gill area. Because of the extremely fine dimensions of the gill sieve some have doubted whether the respiratory current flowed between the secondary lamellae. This is especially relevant as the mean differential pressure across the gills of many fish has been shown to be under 0-5 cm. water (Hughes, i960). In addition to the British marine fishes studied, data are also presented from two freshwater fishes and from the gills of two specimens