The great Sea-cucumber is the largest of all the known European species, and probably one of the largest _Cucumeriæ_ in the world, measuring when at rest fully one foot, and capable of extending itself to the length of three. Under the influence of terror, it dismembers itself in the strangest manner. Having no arms or legs to throw off, like its relations the luidia and the brittle-star, it simply disgorges its viscera, and manages to live without a stomach; no doubt a much greater feat than if it contrived to live without a head. According to the late Sir James Dalyell, the lost parts are capable of regeneration, even if the process of disgorgement went so far as to leave but an empty sac behind. Considering the facility with which the sea-cucumber separates itself from its digestive organs, it is the more to be wondered how it tolerates the presence of a very remarkable parasite, a fish belonging to the genus _Fierasfer_, and about six inches long. This most impudent and intrusive comrade enters the mouth of the cucumber, and, as the stomach is too small for his reception, tears its sides, quartering himself without ceremony between the viscera and the outer skin. The reason for choosing this strange abode is as yet an enigma. [Illustration: Eatable Trepang.] The _Holothuriæ_, which in our part of the globe are very little noticed, play a much more important part in the Indian Ocean, where they are caught by millions, and, under the name of _Trepang_ or _Biche de mer_, brought to the markets of China and Cochin-China. Hundreds of praos are annually fitted out in the ports of the Sunda Islands for the gathering of trepang; and sailing with help of the western monsoon to the eastern parts of the Indian Archipelago, or along the northern coast of Australia, return home again by favour of the eastern monsoon. The bays of the inhospitable treeless shores of tropical New Holland, the abode of a few half-starved barbarians, are enlivened for a few months by the presence of the trepang fishers.