EFORE describing the creatures 

 whose names stand as the title 

 of this chapter, we must glance 

 at a couple of orders collectively 

 known as the Gyinnoglossa, or 

 Naked Tongues, from the fact that the radula (as 

 well as the jaws) is absent. Their true position in 

 the systems of classification is still a matter of 

 contention among the " doctors who differ," but they 

 appear to be closely allied to forms such as Rissoa 

 and Hydrohia, and to have lost their teeth owing 

 to a very distinct change of habit — many of them 

 being parasites. The mouth is developed into a 

 proboscis, used in the parasitic forms for sucking 

 the juices of the host. 



The Eulima-shells (Eulhna) consist of half a dozen 

 native species with polished awl-shaped semi-trans- 

 parent shells that taper to a very fine point, but as 

 the animal in growing has to vacate the older 



