Abstract: | The development of mouth angle sacciform structure was studied in the ontogenesis of hamster Phodopus campbelli. It was found that the true sacciform structure with all components characteristic for adult animals was formed by the 20th day of postnatal development. Histological data have shown than the sacciform structure is formed in ontogenesis as a result of a complex epidermal transformation involving muscular and connective tissues which comprise the external coat. The structure studied is not formed on the basis of sebaceous glands and cannot be assigned to the class of gland as considered before. |