369 

 Dr. Samuel Kneeland, Jr., read the following paper: — 



ON THE ANIMAL OF THE ARGONAUT SHELL, BY DR. JOHN 0. 



WARREN. 



Dr. John C. Warren having obtained, just before his death, a 

 fine specimen of this rare animal, occupying, with its eggs, its 

 shell, intended to take advantage of an early opportunity to 

 exhibit it ; he had illustrated the description of the principal 

 organs by enlarged plates, and had combined in this paper many 

 points of great scientific interest collected from various English 

 and foreign works and journals. He thought that it would be 

 interesting and useful to future observers to have what is known 

 upon this rare animal placed before them at once, as a starting- 

 point for future investigations. 



He had intended to read this to the Society on the evening 

 before his death, which fact w^ill give a melancholy interest to 

 these, his last words to the scientific world. 



The term Argonauta, as applied to a Mollusk, is of modern 

 origin, but the animal to which it is now applied was well known 

 to the ancients ; they, however, in describing what we now call 

 the Argonaut, made use of the word Nautilus. About the time 

 of Linnteus, the ancient term Nautilus was taken from the 

 Argonaut, and given to another molluscous animal, not known to 

 antiquity. 



Aristotle, and the naturalists w^ho preceded him, called the 

 Cephalopod Mollusks Polypi ; an application of the term which 

 at first sight appears strange, but which is, in fact, perfectly cor- 

 rect, as these animals have a great number of feet, — hence the 

 name. This term is now confined to the lowest class of E-adiata. 



The Argonaut belongs to the Cephalopod Mollusks, which 

 have been divided, from the number of their branchige, into the 

 Dihranchiata and the Tetrahranchiata ; to the former the Ar- 

 gonaut belongs, to the latter the Nautilus. The Dibranchiate 

 Cephalopods have their arms provided with suckers, hence they 

 have been called Acetahulifera by D'Orbigny ; the Tetrahran- 

 chiata have none of these suctorial disks, and are inferior in 

 organization to the former. The Dihranchiata are divided 

 according to the number of their arms, into Octo'pods and Deca- 



PROCEEDINGS B. S. N. H.- — VOL. V. 24 AUGUST, 1856. 



