HIPPONYX MITRATA. 61 



'' The next, Brachiopoda, has 



Crania. 



Orhiciila Patella . 



Terebratfi la.. Some from Anomia. 

 Ling Ilia Patella.^^ 



Lucy could not forbear interrupting her father 

 upon hearing the name of Patella. " How can 

 that genus be mixed with the Conchifera ?'' she 

 inquired. 



'* The shell is hiralre,'' he replied ; '' raised 

 upon a fleshy peduncle, and fixed to marine sub- 

 stances; the hinge is without teeth, having the 

 form of a duck's beak ; the colour a greenish tint. 

 It is found near the Molucca isles. 



" Yet more remarkable is the Hipponyx mi- 

 tj'ata, a common shell, known as Patella mitrata, 

 long supposed to be a univalve, the upper valve 

 only being known. A French naturalist disco- 

 vered the lower valve, and botit have one muscular 

 impression in the form of a horse-shoe. 



" I think that it will be best to pause a little 

 before we enter upon the study of the twelfth 

 class, Mollifsca, which contains most of the uni- 

 valves of Linnaeus." 



