J)2G Illustrated Zoological Notices. 



Art. TV. Illustrated Zoological Notices. By Edward Charles- 

 worth, F.G.S., &c. 



1. On the Power which the Animal of the Argonaut has of repairing Breaches 



in its Shell. 



2. On the recent Discovery of a Fossil Crocodile at Whitby. 



3. On a Form of chambered cephalopodous Shells, connecting the Genera 



Nautilus and Ammonites. 



The difference of opinion entertained respecting the legiti- 

 mate tenant of the shell called the Argonaut, or Paper Nauti- 

 lus, has given rise to more interesting discussion, and furnished 

 materials for a greater display of ingenious reasoning, than 

 perhaps any other question that has agitated the philosophical 

 world in connexion with zoology. A doubt may, perhaps, 

 even be hazarded whether the true interests of science would 

 be advanced by a termination of the controversy, either 

 from demonstrating the Ocythoe to be the constructor of 

 its shell, or by discovering the mysterious creature, if such 

 really exist, that frames a habitation for another being, 

 and of whose nature we are as profoundly ignorant as of the 

 animals which inhabited the extinct testaceous genera occur- 

 ring in the rocks of the Silurean system, or mountain limestone 

 series. The researches undertaken for the purpose of arriv- 

 ing at a solution of this obscure problem, whether by direct 

 experiment upon the immediate subject of dispute, or by 

 attempting to discover in allied organisms conditions which 

 shall reconcile the apparently anomalous points in the 

 history of the genus Argonauta, cannot fail to evolve facts 

 more or less interesting when considered in relation to com- 

 parative anatomy and physiology, although the ultimate object 

 of the investigation may never be attained. I had long, in 

 common, probably, with many others, wondered that no series 

 of experiments, similar to those lately instituted by Mrs. 

 Power, and still more recently repeated by Captain Rang *, 

 had not been attempted by some of the naturalists whose 

 opinions and personal observations are on record in reference 

 to the relation existing between the Ocythoe and its shell ; 

 since the power of repairing its dwelling in common with 

 other conchyliferous Molluscs, naturally suggests itself as a 

 simple and satisfactory refutation of the parasitic propensities 

 attributed by many to this Cephalopod. Upon reading Cap- 

 tain Hang's description of the important distinction which he 

 remarked between the original shell and the diaphragm with 

 which the Ocythoe repaired the breaches artificially made in 

 its habitation, it immediately occurred to me that, if both his 



* See Mag. Nat. Hist, for Sept. 1837, p. 393. 



