490 THE VOYAGE OF H.M.S. CHALLENGER. 



insidaris, Keys, Nephila victorialis, L. Koch, Pholcus ancoralis, L. Koch, Tetra- 

 gnatha and Chiracanthium (immature), Heteropoda sp. (immature), Argyrodes sp. ?, 

 Argiope sp., and Attus sp.? The Lepidoptera included the following new species — Xois 

 fulvida, Hypolimnas murrayi, Hypolimnas thomsoni, and Astura fluminalis. 1 The 

 Hymenoptera included one new species, Belenogaster bidentatus. 2 



The natives of Matuku were mostly true Fijians, though there were some pure 

 Tongans amongst them, immediately to be distinguished by their use of the frontal 

 muscles in conversation. There is no doubt also mixed blood in the island. The houses 

 of the people were miserably dirty, and built on filthy black muddy flats close to the sea. 

 A boy was observed to make his way over a mangrove swamp, with remarkable rapidity, 

 by crawling over the tops of the mangrove roots, and thus avoiding the mud below; 

 just as the coast natives in parts of New Guinea are said to traverse the low swampy 

 shore. 



In dredging off Matuku Island, in 310 and 315 fathoms, on a coral bottom, some 

 Phorus, Turritella, and a few other shells were brought up, as well as numerous 

 specimens of the blind Crustacean, Polycheles, and other animals showing the fauna to 

 be a true deep-water one. 



A living specimen of the Pearly Nautilus (Nautilus pompilius), so rarely seen in the 

 living condition by any naturalist, was captured here. This was the only specimen of this 

 animal obtained by the dredge or trawl during the voyage. The animal was very lively, 

 though probably not so lively as it would have been if it had been obtained from a less 

 depth, the sudden change of pressure having no doubt very much disarranged its economy. 

 However, it swam round and round a shallow tub in which it was placed, moving after the 

 manner of all Cephalopods, backwards, that is with the shell foremost. It floated at the 

 surface with a small portion of the top of the shell just out of the water, as observed by 

 Rumphius. 3 The shell was maintained with its major plane in a vertical position, and its 

 mouth directed upwards. The animal seemed unable to sink, and the floating of the 

 shell, as described, was due no doubt to some expansion of gas in the interior, occasioned 

 by diminished pressure. The animal moved backwards slowly by a succession of small 

 jerks, the propelling spouts from the siphon being directed somewhat downwards, so that 

 the shell w T as rotated a little at each stroke, upon its axis, and a slightly greater area of 

 it raised above the surface of the water. Occasionally, when the animal was frightened 

 or touched, it made a sort of dash, by squirting out the water from its siphon with more 

 than usual violence, so as to cause a strong eddy on the surface of the water. On either 

 side of the base of the membranous operculum-like headfold, which when the animal is 

 retracted, entirely closes the mouth of the shell, the fold of the mantle closing the gill 



1 A. G. Butler, Ann. and Mag. Nat. Hist, ser. 5, vol. xi. p. 402, 1883. 



2 W. F. Kirby, Ibid., vol. xiii. p. 410, 1884. 



3 De Amboinsche Rariteitkamer, p. 61, Amsterdam, 1705. 



