BARNACLES—NAUTILUS AND CUTTLES 375 



mentioned long ago by Darwin, barnacles not infrequently attach themselves to 

 marine snakes, but such a remarkable specimen as the one referred to, which was 

 brought alive to the Colombo Museum in 1909, is seldom seen. The barnacles were 

 of two kinds, the one with large white valves and the other with the valves much 

 reduced in size, so that a large portion of the nut-brown body was exposed to view. 

 As the cluster was of large size and considerably wider than even the head of the 

 snake, it must have formed a very serious hindrance in swimming, and thus consider- 

 ably diminished the snake's rate of speed in the water. In this instance the bar- 

 nacles did not derive any special benefit from their association with the snake, and 

 would have flourished just as well on any other floating or swimming object, but 

 the above-mentioned minute barnacles of the genus Stomatolepas are absolutely 

 dependent upon their hosts for food. 



It may be added that in New Zealand waters the shell of a crab of the genus 

 Paramithrax seems to be almost invariably infested by barnacles (Balanus 

 decorus), which are in some cases so numerous and so large as to exceed the crab 

 in bulk. 

 Nautilus and The three species of nautilus, which must not be confounded with 



Cutties. t ne so-called paper-nautilus, are the sole living representatives of the 

 formerly large and important group of cephalopocl molluscs characterised by having 

 four, in place of two, gills, and likewise by possessing the well-known many- 

 chambered shell in the mouth of which are contained the soft parts. The three 

 living species, of which Nautilus pomjyilius is the typical representative, as it also is 

 of the family Nautilidce, are restricted to the tropical and subtropical zones of the 

 Pacific and Indian Oceans, where they live in very deep water. Although 

 specimens of the nautilus with the soft-parts were formerly very rare in 

 collections, it appears probable that the fishermen of certain small islands in the 

 Philippines have been for centuries in the habit of taking nautiluses, which enter 

 their fish-traps at certain seasons of the year in considerable numbers. Hearing of 

 this, an American naturalist made a trip some years ago to Negros Island, where 

 he was successful in obtaining several specimens, and would have got more had his 

 visit been timed at the right season. The traps are sunk in deep water, and the 

 nautiluses enter with the fish. The shells are used locally as drinking-cups or 

 flower-vases, and are sometimes cut into roughly shaped spoons ; while they are 

 also bought extensively by Chinese shopkeepers, who export them to China where 

 they are used as material for button-making. 



The only other living cephalopod furnished with a true shell is Spirula 

 peroni ; these delicate little white pearly shells, each coiled into a flat spiral of 

 little more than an inch in diameter, being strewn in thousands on the shores 

 of New Zealand and some of the Indo-Malay islands. Like the nautilus, the 

 spirula represents a family, the Spirulidce, by itself. The complete animal is 

 very rarely obtained ; but such specimens as have come under observation show 

 that the shell is internal, with a small portion of its outer margin appearing on 

 each side through the body- wall of the mollusc. 



Exception may perhaps be taken to the statement that no cephalopods save 

 the nautilus and the spirula are provided with true shells, since the beautiful 

 basket-shaped shells of the paper -nautilus or argonaut (Argonauta argo) form 



