Standards of morphological development of the quail, Coturnix coturnix japonica, embryo.

The morphologic growth of 290 Japanese quail embryos was analyzed to enable an assessment of the developmental status of an organism and permit the evaluation of experimental effects on development. The growth of 36- to 228-hr embryos was analyzed according to Hamburger and Hamilton's (1951) stages of development for the chick; the growth of 240-hr and older embryos was analyzed by correlating age with the length of 5 morphologic structures, toe, leg, beak, wing, and total. A correlation of +.99 was obtained for age-stage relations and a correlation of +.97 was found for age-structure length relations.