This paper “New Subspecies of the Rodent Baiomys From Central America” was published in 1958 by the University of Kansas Publications, Museum of Natural History Volume 9, No. 15, pp. 397–404. It is a scientific history of the Rodent. The paper focuses on the southern pygmy mouse, Baiomys musculus, which is known as far north as the Mexican states of Jalisco, Michoacán, south of the Mesa Central, east to central Veracruz, and south to western Nicaragua. Previously, two subspecies have been recognized from the southern part of the known range of this species: B. m. nigrescens, blackish mice from Chiapas, México, and Guatemala, and B. m. grisescens, grayish-brown mice from Honduras and western Nicaragua. A study of recently acquired specimens from Guatemala, El Salvador, and Nicaragua reveals two additional subspecies. Read this paper to know about the additional subspecies.