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Slugs are hermaphrodites, having both female and male reproductive organs. Once a slug has located a mate, they encircle each other and sperm is exchanged through their protruded genitalia. A few days later, the slugs lay around thirty eggs in a hole in the ground, or beneath the cover of an object such as a fallen log. Наземные слизни характеризуются гермафродитизмом (иногда последовательным) и перекрёстным внутренним оплодотворением.