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Normal tables of chicken embryo development are used to define specific stages of morphogenetic progression from the first cleavage divisions through hatching. Although established for the turkey and Pekin duck, the application of the normal tables of chicken embryo development to other birds of commercial and research importance needs be examined. Chicken, turkey, Japanese quail, and Pekin duck blastoderms from oviductal eggs showed differences in the rate of development that were inversely correlated with egg size. Oviposited eggs from these and additional species (goose, Muscovy and mule ducks, and Guinea fowl) were examined after 24 to 72 h of storage and at 6-h intervals up to 72 h of incubation. There was variation in the developmental stages of the blastoderm at the time of oviposition between and within the species and strains examined. Although it is recognized that the temporal rate of development will differ between different species and strains, the external features of any embryo in any given stage will be nearly identical.