For some time many investigators have thought that the genus _Zenaida_, which includes the White-winged and Zenaida doves, and the genus _Zenaidura_, which includes the Mourning, Eared, and Socorro doves (Peters, 1937:83-88), are closely related, perhaps more closely than is indicated by separating the several species into two genera. It is the purpose of this paper to report investigations on the musculature of the jaw of doves with the hope that, together with the results of other studies, the relationships of the genera _Zenaida_ and _Zenaidura_ can be elucidated.