Mr. Lovell Reeve on the Pearly Nautilus. 119 



3. Aonyx. Muffle bald, oblong, transverse ; claws rudimentary ; 

 soles half naked. A. Horsfieldii, A. aurobrunnea, A. indigitata of 

 India, and A. Lalandii of South Africa. 



4. Latax. Muffle bald, large, oblong, triangular, angular above ; 

 claws distinct ; soles hairy. L. Lataxina. 



B. Hind feet large. 



5. Enhydra. Tail short, cylindrical ; muffle bald, oblong, trian- 

 gular ; soles entirely hairy. E. marina. 



6. Pteronura. Tail elongate, with a fin on each side. P. San- 

 bachii. 



XXII. — History and Observations on the Pearly Nautilus, 

 involving a new Theory to account for the earner ated con- 

 struction of its Shell by the aid of the Siphonic Membrane. 

 By Mr. Lovell Keeve, A.L.S. * 



The two great conchiferous Cephalopods, Argonauta and 

 Nautilus, seem to have been equally well known to the father 

 of natural history ; for in Scaliger's translation of the ' Hi- 

 storia Animalium' we learn that Aristotle, when speaking of 

 his Polypi, or Cephalopodous Malakia, makes especial mention 

 of two of them having shells. They were both regarded by 

 this venerable philosopher as species of Nautilus ; u the one," 

 says Aristotle, " has a hollow shell, not naturally adherent to 

 it ; the other has a shell, which like a snail it never quits. 55 

 Here, however, remained the history of these mollusks for 

 ages. Pliny, and indeed other writers subsequent to Aristotle, 

 seem only to have noticed one of the Nautili of their prede- 

 cessor, for their observations embody little beyond what he 

 had transmitted to them of his Nautilus primus, the light rao- 

 nothalamous Argonaut of Linnaeus. The Nautilus secundus of 

 the ancients remained in obscurity until the revival of letters ; 

 Belon, a French author of 1550, gave a representation of the 

 shell ; and its animal inhabitant was figured in 1 703 by Rum- 

 phius, a Dutch merchant and naturalist resident at Amboyna. 

 Although an accurate delineator of character for the age in 

 which he lived, he w r as no anatomist, and his drawings are 

 somewhat inaccurate ; having lost his sketches, he is said to 

 have renewed them from recollection ; they have, however, 

 been valued from necessity, for no other living specimen of 

 this mollusk was discovered for the lapse of a century and a 

 quarter. 



Cuvier, the first great anatomist who tested the organism 



* From Mr. Lovell Reeve's valuable work on the Mollusca. 



