IANTHINA. 457 



view, on the plea that one intermediate family would be less 

 repugnant to the feelings of couchologists, and even of some 

 malacologists, than the adoption of five families, or the creation 

 of five sections of essentially the same malacological structure. 

 However great may be the disapprobation of naturalists at 

 these changes, we feel it to be our duty to see that nature is 

 satisfied before conchological hypothesis, and we fearlessly 

 invite malacologists to point out a more natural site for these 

 creatures, than as a united anomalous group, immediately 

 abutting on the Muricidal tribes. 



This family will conspicuously illustrate the great advan- 

 tage, nay even the triumph, of malacological facts over con- 

 chological considerations, and point out the little reliance to 

 be placed on the form of the hard parts as distinctive charac- 

 ters. What conchologist would have ventured to associate 

 these anomalous genera in the same circle? Conchology 

 could never have given to these singular objects an appro- 

 priate constitution : without the assistance of malacology they 

 would for ever have remained a nomadic tribe, and indefinitely 

 the sport of hypothesis. 



IANTHINA, Lamarck. 



This singular genus appears not to be indigenous to any of 

 the coasts of our globe ; it has a truly oceanic habitat amidst 

 the mighty waters of the Atlantic and Pacific ; but the various 

 species are occasionally wafted to the different shores of the 

 world. More than twenty years ago, many of the lanthina 

 communis were brought to us alive, though collapsed, collected 

 on the South Devon coasts ; but I believe none have appeared 

 since in those localities. 



This genus has long caused embarrassment to naturalists, 

 and is still a source of difficulty in regard to the structure of 

 the animal and its natural position ; but I think the obstacles 

 to a true determination will disappear on attentive consider- 

 ation. The great stumbling-block is the float, as it is called, 

 or vesicular mass attached to the foot, which has been con- 

 sidered an hydrostatic apparatus. This idea is erroneous : 



