142 UTILIZATION OP MINUTE LIFE. 



Nautilus and the beautiful Argonauta, or Paper 

 Nautilus, which is not unfrequently seen, on calm 

 days, gliding softly on the surface of the blue Medi- 

 terranean, and of which Pliny, Buffon, and others 

 have given such poetical descriptions. Their shells 

 are sought for as ornaments. Other species, such 

 as certain rare Carinaria, produce magnificent shells, 

 which sell at a high price for drawing-room orna- 

 ments. 



The Nautilus pompilius, according to some natu- 

 ralists, is seen floating on the waters of the Atlantic 

 between the tropics; the Argonauta Argo on the 

 Mediterranean ; the Carinaria fragilis also inhabits 

 the Atlantic; whilst G. vitrea, a rare species, is 

 chiefly found in the South Seas. 



In the second order of Mollusca, named Gaste- 

 ropoda, we have some very interesting, useful, and 

 ornamental animals. To save space and time required 

 for minute description, the common Garden Snail 

 or Slug may be taken as an example of the order 

 of Gasteropoda. The species of this large tribe are 

 very numerous, and perhaps as beautiful or as 

 useful as numerous. 



I shall mention, in the first place, the Gastero- 

 poda from which the ancients extracted the colouring 

 matter known as Tyrian purple. This magnificent 



