CHAPTER IV. 



TRANSPLANTATION OF UNIVALVES. 



Operculate water-snails, it seems possible, may some- 

 times be transported while clinging by" closure of the 

 operculum to the legs of aquatic creatures of certain 

 kinds. Water-beetles and other such animals, walking 

 amongst the branches of aquatic weeds or upon the 

 mud at the bottoms of pools and slow-flowing rivers, 

 must occasionally insert their legs into the mouths of 

 these shells, and, if the operculum be quickly closed, 

 the mollusc may possibly cling firmly, and may be 

 carried about by a sufficiently strong animal for a 

 considerable time. A large and strong-flying water- 

 beetle, in such a case, might obviously carry a shell of 

 small size from one piece of water to another. One 

 little observation, more or less apposite, has been made, 

 the aquatic larva of a dragon-fly having been seen by 

 Mr. Hardy in May, 1890, with one foot firmly held 

 between the operculum and lip of a specimen of 

 Bythinia tentaculata, and it is interesting to find, also, 

 that a humble-bee has been seen with an operculate 

 land-shell holding on to one of its legs in a similar 



