RELATION OF BIOLOGY TO GEOLOGICAL INVESTIGATION. 347 



Diceca — Continued. 

 OEDER RHIPHIDOGLOSSA— Continued. 



Turbinidse 



Liotiidae 



Trochidse 



Stomatellidae .... 

 Pleurotomariidse. 



Scissurellidse 



Haliotidae 



Fissurellidse 



Emarginulidre . . . 



Brackish. 



Fn-sli 



ORDER DOCOGLOSSA. 



Acmaeidae". 

 Patellidae . 

 Lepetida' . 



AciiiM'iihi' 



Acmaeidae. 



( (tinida? 



Auriculidae . . 

 Siphonariidse . 

 Gadiniidae .'. .. 

 Amphibolidae. 



ORDER POLYPLACOPHnRA. 



Pnl mon if era. 

 ORDER Pl'I.MONATA. 



Otinidae 



Auriculidse . . . 

 Siphonariidse. 

 Gadiniidae . . 

 Amphibolidae. 



Chilinida-. 

 Physidae. 

 Ancylidae. 

 Limnaeidae. 



Opisthobranchiata. 

 ORDER TECTIBRANCHIATA. 



Philiuidae 



Amphyspiridae - . - 



Ringiculidae 



Actseonidae 



( !ylinchnidae 



Bullidae 



Ampluatridae 



Lophoeercidae 



Aplysiidae 



Runcinidae 



1 yliidinidie 



Umbrellidse 



Pleurobran< hiidae. 



