p
4
F
5
Fig. 2. Electrocardiograms ( A ) and ventricular resting and action potentials ( B ) recorded from the heart of the rainbow
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trout, Salmo guirdneri, and the frog, Rnnn pipiens (Bennion, 1968). From D. J. Randall (1968), Am. Zoologist 8, 179-189.