On day 26 the differentiation of the epithelium was almost completed. The surface epithelium differentiated into the interfollicular epithelium(IFE) and the follicle-associated epithelium (FAE).

• 26天胚上皮分化基本完成,表面上皮分化为滤泡间上皮(IFE)和连滤泡上皮(FAE);