The midgut gland cell differentiation occurs at Z2, There are 4 types of cells, i. e., embryonic cell (E-cell), fibrillar cell (F-cell), blister cell (B-cell) and resorptive cell(R-cell).

中肠腺小管上皮在Z2期胞已有了分化，由4类胞组成，即胚胞(E胞)、维胞(F胞)、泡胞(B胞)和吸收胞(R胞)。