Martin, P. S., and Harrell, B. E.

1957. The Pleistocene history of temperate biotas in Mexico and eastern United States. Ecology, 38(3):468-80, 15 figs., 2 tables, July.

Maslin, T. P.

1959. An annotated check list of the amphibians and reptiles of Colorado. Univ. Colorado Stud., Ser. Biol., 6:vi + 98 pp., November.

Mattox, N. T.

1936. Annular rings in the long bones of turtles and their correlation with size. Trans. Illinois St. Acad. Sci., 1935, 28(2):255-56, March.

Meek, S. E.

1904. The fresh-water fishes of Mexico north of the Isthmus of Tehuantepec. Field Columbian Mus. Publ. 93, Zool. Ser., 5:lxiii + 252, 72 figs., 17 pls., 1 map, August.

* Mertens, R.

1928. Über die einwirkung der kulturlandschaft auf die verbreitung der amphibien und reptilien. Zool. Garten Leipzig, N. S., 1(Pt. 5-6): 195-203 (from Biol. Absts., and Stejneger, 1944:47).