Glossogobius brunneus is a large goby distributed from the coasts of tropic to central Japan. It lives on the bottom in brackish or shallow waters, hidden under the stones or weeds. It spawns in summer extending from the end of July to the beginning of September. The eggs are fixed to the under surface of stones or piles and guarded by the male, who aerates them by keeping up a flow of water over the spawn through the action of his dorsal fin, of which length is more longer than that of the female. The embryo is kept in an elongate and pyriform egg-shell which measures about 3•5mm in length. When the eggs are laid, a tuft of adhesive threads, with which they are attached in cluster to various objects, appears at the narrow end of the shell-membrane (See Figs. 2 and 3). It is seen to be a minute branch of outer shell-membrane. The embryo is hatched about in 80 hours after the egg being spawned at water temperatures of 26°C. The newly hatched fry measures about -2•07mm in total length. The favorable salinity for normal development of the eggs ranges from 10 to 22‰.