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Show 8 ON A ZOOLOGICAL EXPEDITION TO THE SOUTH SEAS. [Jan. 17, but I captured four specimens of Gtenoplanal, which yielded a number of results of some interest. This remarkable form, half Ctenophore and half Plathelminth, had previously only been obtained as a unique specimen by the Russian naturalist Korotneff, off the west coast of Sumatra in 1886. Korotneff's account was inaccurate in many details, and his discovery of the type was regarded with some scepticism. M y re-discovery of this creature is therefore matter of satisfaction. All four specimens were taken from a drifting cuttle-bone off the Conflict Lagoon in the Louisiades, British N e w Guinea. From the Deboyne Lagoon, in the same Archipelago, I obtained a species of Ampliioxus belonging to the subgenus Asymmetron, previously known only from the West Indies. This is a remarkable fact of distribution, since in the Torres Straits, which are comparatively close by, there are two species of Ampliioxus belonging to other subgenera. When I revisited N e w Guinea on m y return for the second time to New Britain, I was fortunate in securing the only specimen ever seen of the animal of Nautilus umbilicatus, which had been taken from the surface off the East Cape of British N e w Guinea. Nautilus does not come to the surface normally according to my observations, and all specimens which are taken from the surface are probably in a moribund condition. This was the case with the specimen obtained by Dr. Bennett, upon which Sir Richard Owen based his classical work on Nautilus. M y object in changing m y locality from time to time was for the purpose of finding a place where Nautilus could be more easily got at. After much misgiving and disappointment, I at last found such a place-namely, Sandal Bay, Lifu, in the Loyalty Group. In this place Nautilus migrates at night from deep w7ater into as little as three fathoms. It comes quite close to the shore. The species occurring here is N. macromplialus. So far as I have ascertained at present, this species only differs from N. pompilius in the character of the umbilicus of the shell. The animals are almost identical. N. umbilicatus differs strikingly in external appearance from both of the preceding. After an absence from England exceeding two years, I induced Nautilus to deposit its eggs in m y cages. The eggs are firmly fixed to a suitable surface: the best artificial surface which can be offered to the Nautilus is sacking, the fibres of which are entangled in the hardened milk-white capsule of the egg. I have described these eggs in the ' Proceedings of the Royal Society' (1897). Neither in Lifu nor subsequently in N e w Britain, where I got the eggs of N. pompilius, was I able to rear embryos from the deposited eggs-such was the effect of captivity. The geographical distribution of N. macromplialus is interesting. It is confined rigidly to the N e w Caledonian Archipelago. In the neighbouring N e w Hebrides and in Fiji, N. pompilius is again met with. 1 See Q. J. M. S. vol. xxxix. 1896, p. 323. |