1931. A study of the teiid lizards of the genus Cnemidophorus with special reference to their phylogenetic relationships. Bull. U. S. Nat. Mus., No. 154, pp. viii + 286.

Contreras A., A.

1942. Mapa de las provincias climatologias de la Republica Mexicana. México, D. F., Dirección de Geografía, Meterología e Hidrología, pp. i-xxviii, tables 1-54, 2 maps.

Cooke, C. W.

1945. Geology of Florida. Florida Geol. Surv., Geol. Bull., No. 29:1-339.

Dorf, E.

1959. Climatic changes of the past and present. Contrib. Mus. Paleo. Univ. Michigan, vol. 13 (8):181-210.

Duellman, W. E.

1956. The frogs of the hylid genus Phrynohyas Fitzinger, 1843. Miscl. Publ. Mus. Zool. Univ. Michigan, No. 96:1-47, pls. 1-6.

1958a. A monographic study of the colubrid snake genus Leptodeira. Bull. Amer. Mus. Nat. Hist., vol. 114:1-152, pls. 1-31.