274 MARIKK ANIMAT.S. 



consequence of familiar acquaintance with an interesting and beautiful object, 

 that we at once wish to be better acquainted with it. To dispel, in some 

 measure, this reproach upon our literature, is one aim of ray humble efforts, 

 and if I succeed in the least, it must be much more attributable to my 

 love of the subject, than my ability, 'ab initio,' to handle it. 



Well then, we all know the Nautilus' shell when we see it, but we often 

 mistake the same species of shells for varieties, from a very simple circum- 

 stance, namely, the manner in which they are prepared to form ornaments 

 for our boudoirs and mantles. The common Argonaut, or Nautilus, is of a 

 cream-colour, with an enamelled surface, plain on the larger part, and 

 where it begins sensibly to decrease, covered with transverse bars and 

 wavings of a cinnamon-colour, with a large portion of a very deep hue, in 

 fact nearly black at the smallest end. Now, like all shells, this is likewise 

 composed of Lamina, which have, in the upper ones at least, somewhat of 

 a cellular structure; though in this instance the material is so compact and 

 thin, that it is not so easily recognised as in the Pinna and Mi/tilus tribes. 

 This forms the upper or apparent layer; immediately under this lies one of 

 true Nacre, or Mother of Pearl, which more or less extends in several layers, 

 through the remainder of the entire thickness, and is of a very beautiful 

 surface and appearance; hence, the upper or cream-coloured and cinnamon- 

 barred enamelled surface has only to bo removed, which is very easily done 

 by a strong acid, to render the whole shell a nacreous or pearl shell; and 

 this is the condition in which we see it when formed into those elegant 

 cups, or vases, or stands, so often seen among the more choice articles of 

 veiiu. 



There are a great many species of Argonaut, of which I may speak in a 

 future paper, but I shall now confine myself to general observations. When 

 I speak of the upper layer being enamelled, I must be understood to mean 

 the whole upper surface of the shell, both on the outside and inside; and 

 hence the nacreous formation comprehends the whole interior, bearing the 

 same relation to the enamelled layers, as the loaves of a book bear to the 

 covers. When a section is made of these shells lengthwise, they discover to 

 the view a series of cavities of a wedge-like figure, somewhat hollowed on 

 the under side, which shape is formed by the circular shape of the shell; 

 and through the centre of each of these cavities, and the layers of shell 

 which divide them from each other, a tube passes, which is the apparatus 

 by which the Nautilus rises to the surface of the water, or sinks to the 

 bottom. This is performed in the following manner: — The tube thus running 

 through these cavities is capable, at the will of the Argonaut, of sucking in 

 or imbibing, or ejecting water; and hence, when the creature is on the surface 

 of the sea, and desires to sink, it has nothing to do but to imbibe water into 

 these cavities, and, like a boat filling, it necessarily sinks; and again, when 

 at the bottom and desiring to rise, it ejects the water thus imbibed, and 

 thus necessarily rises, by reason of the air which is always resident in the 



