PALEONTOLOGY 



MACELLANIN/E. 

 (Austral) 



Magellan!* 

 (Cainoxoic Recent) 



DALLININ/C 

 (Boreal) 



Dallina 

 (Cainoxoic - Recent) 



Terebralella 

 (Jurassic -Recent) 



Magas 



(Cretaceous) 



Meaerlina 

 (Recent) 



xris [Argiope] 

 (Jurassic Recent) 



Cistella 

 (Cretaceous-Recent) 



Trigonosemus 

 (Cretaceous) 



Magasella MEGATHYRIN>t Muhlfeldtia . 



(Recent) (Jurassic-Recent) 



Ismenia 

 (Jurassic) 



Platidia 

 (Recent) 



Zeana 

 (Jurassic) 



FIG. 10. EVOLUTION OF THE LOOP IN LONG-LOOPED 

 TEREBRATULACEA. 



Loop in outline, septum black. (After Beecher.) 



