Black dogfish to the clade formed by the granular dogfish ("C. granulatum") and combtooth dogfish ("C. nigrum"). The black dogfish is a common species, with a wide but discontinuous distribution in the temperate waters of the Atlantic Ocean; its range abuts, but does not extend into, the Arctic Ocean. In the northeast, it occurs from Iceland to Sierra Leone, including the Faroe Islands, southern Norway, and the Rockall Trough and Porcupine Seabight off Ireland. In the northwest, it is found from southern Greenland and Baffin Island to Virginia, being particularly abundant in the Laurentian Channel, and may occur further south to the
Rockall expedition made a brief attempt to return to the ship, but could not find the frigate in the haze, and soon gave up and returned to Rockall. After the haze became a fog, the lookout sent to the top of Rockall spotted the ship again, but it turned away from Rockall before the expedition in their boats reached it. Finally, just before sunset, the frigate was again spotted from the top of Rockall, and the expedition was able to get back on board. The crew of the "Endymion" reported that they had been searching for five or six hours, firing