LECTURE XI. 163 



"Among the principal miracles of Nature 

 (says he) is the animal called Nautilos or Pompi- 

 los. It ascends to the surface of the sea in a su- 

 pine posture, and gradually raising itself up, forces 

 out, by means of its tube, all the water from the 

 shell, in order that it may swim the more readily ; 

 then throwing back the two foremost arms, it dis- 

 plays between them a membrane of wonderful te- 

 nuity, which acts as a sail, while with the remaining 

 arms it rows itself along ; the tail in the middle 

 acting as a helm to direct its course : and thus it 

 pursues its voyage j and if alarmed by any appear- 

 ance of danger, takes in the water and descends." 



The Paper Nautilus is an inhabitant of the 

 Mediterranean and Atlantic seas. In the Indian 

 seas is found a species so similar that it has gene- 

 rally been considered as a variety : it differs in 

 having the shell marked into numerous slight tu- 

 bercles on each side the furrows. This is the va- 

 riety described by Rumphius, in his account of 

 its inhabiting animal, observed by him during his 

 residence at Amboyna. There are other species 

 and varieties of this genus, which the short limits 

 of our lectures will not permit us to particularize. 

 I shall only observe that the supposed species, so 

 much celebrated under the title of the glass Nau- 



