Clitellum

The clitellum is a thickened glandular and non-segmented section of the body wall near the head in earthworms and leeches, that secretes a viscid sac in which the eggs are deposited. It is present about 2 cm (0.79 in) behind the anterior end of the body (around the 14th, 15th and 16th segments). Its main function is to store the eggs of the worm.