Abstract：The location,morphology,microstructure and ultrastructure of the androgenic gland in swimming crab Portunus trituberculatus were studied under zoom stereo microscope,histological section and electron microscope. The results showed that a pair of androgenic glands was found on the surface of the ejaculatory duct. The cytological development of the irregular cord-shape gland can be distinctly divided into three stages:proliferation phase,synthesis phase and secretion phase. The gland secreted in a holocrine fashion,and had two types of cells:type A,whose nuclei were rich in euchromatin,mitochondria and rough endoplasmic reticulum,and type B,which had nuclei rich in heterochromation,and showed karyopyknosis. In proliferation phase the androgenic glands were short and the glandular cells were of small amount,and had a distinct cell boundary. In synthesis phase,the androgenic glands were bigger in size than that in the proliferation phase. The glands with more type A cells appeared like a cord-shape,and had well-developed endoplasmic reticulum and mitochondria. In the prophase of the secretion phase,the androgenic glands were still big with more type B cells,and in the anaphase of the secretion phase,the androgenic glands were smaller in size,and some were broken down. There were many vacuoles in the glandular cells.
