nophis proximus and Natrix rhombifera. Comp. Biochem. Physiol. 35:439449. MOBERLY, W. R. 1968a. The metabolic responses of the common iguana, Iguana iguana to activity under restraint. Comp. Biochem. Physiol. 27:1-20. 1 968b. The metabolic responses of the common iguana, Iguana iguana, to walking and diving. Ibid. 27:21-32. MULLEN, R. K. 1967. Comparative electrocardiography of the Squamata. Physiol. Zool. 40: 114-126. SAINT-GIRONS, H. AND M. C. SAINT-GIRONS. 1956. Cycle d'activit6 et thermoregulation chez les reptiles (lezards et serpents). Vie et Milieu 7:133-336. i ifera. i l. : . TUCKER, V. A. 1967. The role of the cardiovascular system in oxygen transport and thermoregulation in lizards. In: Lizard ecology, a symposium. Wm. W. Milstead, ed., pp. 258269. Univ. Missouri Press, Columbia, Mo. WRIGHT, A. H. AND A. A. WRIGHT. 1957. Handbook of snakes of the U. S. and Canada. Com-
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Walter Auffenberg (1971) studied this question.