346 



SUBKINGDOM MOLLUSCA. 



ing its prey with its terrible armature (odontophora) or tooth- 

 ribbon, analogous to the band of a chain saw, and set with 

 adamantine teeth, sharp-edged, and pointed as those of a shark. 



Mg. WJ. 



Teeth of Murex. 



Cyprom tigris. J. 



The Cyprseid3e~(Cowries) have the mantle, in many spe- 

 cies, covered with filaments and the foot enormously devel- 

 oped. The eyes are near the base of the tentacles, and the 

 tooth-ribbon is armed with a series of powerful teeth. 



The HarpidsB (harp-shells) are found on the shores of 

 the Mauritius, and are remarkable for having too large a 

 foot wholly to conceal within the shell. 

 The Haliotid.se (sea-ears) have shells of a pearly lustre, 

 with resplendent metallic hues, useful for 

 inlaying the darker woods and for sleeve- 

 links. 



The Fissurelidse (fissured) have an 



aperture in tlie top, and, adhering to the 



rocks, seem adapted 



to a sedentary life. 



The Dentalidae (toothed) have 



shell shaped like a miniature elephant's 



tusk. At the base of the conical foot is situated the head. 



Fig. hS3 



Fig. las. 



DentaRum dentSlis. 



ORDER PULMONIFERA. 



G-eneral Characteristics. — The Pulmonifers (lung- 

 bearers) are air-breathing, even those inhabiting the water 

 being obliged to come frequently to the surface. They have 



