594 



THE CHAMBEKED NAUTILUS. 



the only known living representative is the Chambered or Pearly 

 Nautilus. 



While the animal still lives the short tubes that pass through the 

 walls of the chambers are connected by membranous pipes, and even 

 in a specimen that has long been dead these connecting-links hold their 

 places, provided the shell has not been subjected to severe shocks. In 

 one of these shells now before me, which I have very cautiously opened, 

 the whole series of membranous tubes can be seen in their places, black 

 and shrivelled externally, but perfect tubes nevertheless. 



The color of the shell is very beautiful. The ground is white, over 

 which are drawn, as with single dashes of a painter's brush, sundry 



bold streaks of reddish 

 chestnut, mostly coales- 

 cing a])ove, and reach- 

 ing nearly to the centre 

 of the spiral. This por- 

 celain-like material is, 

 however, only an outer 

 coat laid on the real 

 pearly substance of the 

 shell, which is seen on 

 looking into the hollow 

 or into any of the cham- 

 bers. The Chinese avail 

 themselves of this double 

 coating, and, with the untiring perseverance of their laborious nature, 

 take the greatest trouble to spoil the finest shells by covering them with 

 their grotesquely unperspective carvings of figures and landscapes, cut 

 so as to relieve the deep color of the raised figures by the white, pearly 

 background. Unlike the shell of the argonaut, which is almost as frag- 

 ile as if made of sugar, that of the Nautilus is firm and strong, and 

 will bear a considerable amount of rough handling before betraying 

 any signs of injury. 



The order which now comes before our notice is composed of animals 

 which crawl upon a broad muscular organ, termed, from its use, the 

 foot. It is an enormously large order, containing all the snails, wheth- 

 er terrestrial, aquatic, or marine, the whelks, limpets, and similar ani- 

 mals not so familiarly known. Many species are much used as food, 

 while others are of great service in the arts, furnishing employment to 

 many hundreds of workmen. As the shell of these creatures consists 

 of one piece or valve only, they are sometimes termed Univalves, in 

 contradistinction to the oysters, mussels, scallops, and similar shells, 

 which are termed Bivalves, in allusion to their double shell. 



There is a structure belonging to these animals which must be de- 



The Chambered Nautilus (Nautilus Poinpilim). 



