( 241 ) 



Of' aragonite consisted : 

 Cardium (recent and pliocene) 

 Ensis (recent and pliocene) 

 Donax (recent and pliocene) 

 Tellina (recent and pliocene) 

 Astarte (pliocene) 

 Cardita pliocene) 

 C\ therea' (recent) 

 Venus (recent) 

 Inio (recent) 



Mactra (recent and pliocene) 

 My a (recent) 



Corhula (recent and pliocene) 

 Pholas (recent) 

 Scalaria (recent) 

 Natica (recent) 

 Cypraea (recent) 

 Turritella (miocene' 

 Cancel laria (miocene) 

 Cassidaria (miocene) 

 Gerithium (recent) 

 Mu rex (recent) 

 Conns (recent and miocene) 

 Trochus (recent) 

 Turbo (recent) 

 Bulla (recent) 

 Strombus (recent) 

 Ficula (recent) 

 Terebra (recent, miocene) 

 Niso (miocene) 



Dentalium (pliocene, miocene and oligocene) 

 Ringicula (miocene) 



On looking through the above list it is evident that a great deal 

 of the examined Lamellibranchiata consists of aragonite though among 



the fossil species enough calcite shells occur. A specimen of the 

 miocene Cytherca incrassala consists without any doubt of calcite 

 and a specimen of the recent Cy therea meretrix consists with the 

 same certainty of aragonite. Such was also the case with the miocene 

 Venus multilamellosa and the recent Venus albina. Among the 

 Gastropoda shells the majority consists of aragonite but four shells 

 form an exception. For the fossil specimina of Aporrhais and Ancil- 



