Printed in Great Britain GILL DIMENSIONS FOR THREE SPECIES OF TUNNY

(1969) have made a serious effort to determine the relation between size and area within single species. Price reported that for Micropterus dolomieu the total area was related to body weight by the power of 0-78. For the roach and several other species, Hughes and Morgan have found that the relationship is closer to the power of 0-9. For the large number of species ranging from 'sluggish ' to 'active ' that he examined, Gray (1954) reported about an order of magnitude of range in the total gill area per gram of fish, but specimen size varied considerably. I. E. Gray (personal communication to G.M.H., 1959) has pointed out that it is important to compare fish of approximately the same size. In his 1954 paper he included Scomber scombrus and Gymnosarda alleterata ( = Euthynnus alletteratus) and has also reported (personal communication to G. M. H.) data on the blackfin tuna and the yellowfin tuna. Except for this preliminary work, few studies appear to have been reported on members of the genus Thumtus, which is of considerable interest as it includes some of the largest and most active teleosts. In these forms it is clearly of interest to determine how the respiratory area compares with that of other fishes. It is also of interest to see whether the study of gill dimen