XXIX 



The Linnaean cliarafters certainly take in the whole 

 of the land (hells we are acquainted with, except thefe, 

 and one or two others ; but befides the difference in the 

 number of tentacula, and fituation of the eyes, the cir- 

 cumRance of the aquatic teftacea being inhabited by ani- 

 mals of different fexes, and not hermaphrodites, as in 

 the mollufca Liviaces, and fuch as inhabit mod land 

 fhells, have never been thoroughly attended to. Thefe, 

 however various, have generally been confidered to 

 come indifcriminately within the Limax genus ; as fuch 

 we fliall leave them at prefent, this work being profeffed- 

 ly on (liells, and not on their animal inhabitants, more 

 than is fufficient for fpecific purpofes. 



At the end of this, we have fubjoined a plan of Mul- 

 ler's arrangement of univalve teftacea by the animal, 

 in order to fhew to what great variety the Linnaean Li- 

 max is extended. 



6 SPIO. 



Body projefting from a tube, jointed, and furnilhed 

 with dorfal fibres : peduncles rough with briftles, and 

 placed towards the back : feelers two, long, fimple : 

 eyes two, oblong. 



The Sino inhabits S ibella : one or two fpecies on our 

 coafts very minute, the cafes, not defcribed under the 

 article Sabetta, being invifible to the naked eye. 



7 AMPHI- 



