CHAPTER VIII: THE CHAMBERED NAUTILUS 



Family NAUTiLiDi^ 



Shell with few whorls, overlapping more or less ; septa 

 simple ; siphuncle nearly central ; aperture wide. 



Five fossil genera and one living genus constitute this family. 



Genus NAUTILUS, Linn. 



Shell a flat spiral, pearly, with yellowish outer layer, cross- 

 banded with brown; chambers small, except outer one; septa 

 pearly, concave; siphuncle, a membranous tube, central, passing 

 through each septum; body, size of a fist; head conical ; jaws 

 two, strong; tentacles nearly one hundred, unlike, in four groups 

 on thick bases ; hood formed by union of two tentacles ; siphon 

 formed of two overlapping lobes; eyes large, lateral; organs 

 of smell, small tentacles. Distribution world-wide in deep seas. 



Of this genus alone, six hundred extinct species are already 

 distinguished by fossil remains. Only six species are living 

 to-day. Of these but one is abundant or well known. 



The Chambered Nautilus (A'. Pompilius, Linn.; has a 

 large flattened spiral shell, four to six inches in diameter, which in 

 adults has two and one-half coils. It is gracefully turned and deli- 

 cately built, pearly within and porcellanous outside, the yellowish 

 ground of the exterior marked with reddish-brown cross-bands 

 or stripes, variously branched. Opposite the opening of the shell 

 the coil bears a large patch of black. There is a narrow band of 

 black lining the edge of the opening. 



In New Guinea the market value of bright, perfect shells is 

 fully appreciated. Curio-hunters will often discover that by pay- 

 ing a good price they have rewarded the wily and industrious 

 native for his pains in restoring, by judicious use of paints and 

 dyes, the faded glory of a wave-worn shell. Oftener the shell 

 is cleaned by having all the outer coating removed, so as to show 

 only pearl throughout. 



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