A series of enigmatic trace fossils from the Silurian Chaleurs Group (Gascons Formation) of the southeastern Gaspé Peninsula, Quebec, is described in detail. Two types of trace fossil are present and are herein referred to as Form A and Form B. Form A burrows are essentially horizontal branching tunnel networks, typically showing Y-shaped branching patterns and 'turn arounds'. It is suggested that the burrows are feeding and dwelling burrows of some unknown arthropod group, possibly primitive crustaceans. Form B burrows are vertical bulbous structures consisting of an enlarged spherical or subspherical bulbous base which extends upward into an upward tapering vertical shaft. It is suggested that these structures may represent brood structures of the same arthropod group, tubules on the bulb representing juvenile migration exits and tubercles possibly representing poorly preserved and incomplete migration exits or alternatively repositories for fecal material.