No abstract

No abstract

THREE FIQVRESQuestions regarding the mechanism by whicli marine mammals maintain tlie body salt concentration a t a level scarcely higher than that of terrestrial mammals, have been raised by a number of authors. All of the several estimates coxicerned with this problem (Irving et al., '35 ; Smith, '36; Krogh, '39, pp. 165-168 ; Fetcher, '39) agrce that marine mammals feeding on teleost and other mammals are assured of sufficient water from their food a t a low enough salt concentration to require no other osmotic organ than the kidney. The estimates made by Krogli and by one of us, that take into account the higher salt concentration of marine invertebrates, do not agree on this point for those cetaceans subsisting on them. Krogli concludes that the kidney does all the necessary osmotic work. The osniotic situation confronting a. fasting (and especially a fasting, lactating) cetacean has not been scrutinized.It, is the purpose of this communication to discuss the results of an application of the experimental method to the question. A foundation for this work has been laid by previous analyses of blood, muscle, niid other tissues from living bottle-nose dolphins, Tursiops truncatus, (Eichelberger et al., '40 a, '40 b, '40 c) . EXPERIMEBTAL

No abstract