1. Babcock, H. L., Proc. Zool. Soc. Lond., A, 107, 595 (1937).
2. Barbour, T., “Naturalist at Large” (Little, Brown and Co., Boston, 1943).
3. Carr, A. F., “Handbook of Turtles” (Cornell University Press, Ithaca, New York, 1952).
4. Murphy, R. C., Copeia, No. 2 (1914).
5. Lane, C. E., and Eleanor Dodge, Biol. Bull., 115, 219 (1958).