UNIVALVES ARGONAUT A. 69 



sive thinness, brittleness, and lightness. The Argonauta 

 argo, usnally known by the name of the paper nautilus, 

 is the identical shell supposed in the early ages of society 

 to have first taught men the use of sails. 



A mucilaginous animal, called poulpe*, is often mis- 

 taken for the paper-nautilus ; it is seen sailing on the ocean 

 with its arms erect, and a membrane thrown out between 

 them, by which means it is driven forward, like a vessel 

 under sail. The Mediterranean often has whole fleets of 

 these diminutive navigators floating on its calm surface. 



Thecolor of the Argonauta: is mostly blueish, or yellow- 

 ish white, having the keel often tinged with a brownish 

 hue. As to size, the Argonautae differ greatly ; the argo, 

 for instance, will often grow to ten or twelve inches in 

 width; whereas the cornu and arctica seldom exceed 

 three or four lines in diameter. 



The Mediterranean and Indian seas produce some va 

 rieties; others are from the Cape of Good Hoj)e, and 

 some inhabit the Northern and Greenland seas. 



None of this genus have hitherto been found fossil. 



They are supposed to have derived their name from 



ARGONAUTA— Pa^er Sailor. 



Argo {Paper Nautilus) Cymbiuni {Minute P. S.) 



Vitreus. Cornu. 



Arctica. 



* Mr. Mawe in his «' Sliell Collectors' Pilot" has given an ac- 

 count of this animal, which had before been supposed to belong to 

 the Argonauta Argo. 



