The histology and development of the oviduct of unpaired female canaries during the natural breeding season were examined. The histology resembles that of the fowl. The tubular glands develop by invagination of the epithelial cells, and albumen granules subsequently form in their cytoplasm. The epithelium differentiates into ciliated columnar cells and goblet cells. The histology of the magnum is uniform along its length at all stages of development.
Oviduct development is closely correlated with that of the ovary. In its early stages there appears to be little correlation between oviduct development and that of the brood patch or of nest-building. The formation of albumen coincides with the enlargement of one ovarian follicle more than the rest, the completion of defeathering, and intensive nest-building behaviour.