83 



Table shoioing approximatehj the Icnoivn di.ifribuiion of the chief groups of Brachicjioda in 



geological time. 



Tebebkatulidje. . 

 Terebrotula, Miiller. 

 Centrov/ella^ Billings. 

 Vitulina, Hall. . . 

 Tropidoleptus, Hall . 

 Meganteris, Suess . 

 Epithyris, King^ . 

 Waldhcimia Kin<: (=Eudesia) 

 Lyra, Cumberland . 

 Pycjope, Link . 

 Orthotoma, Qiienstedt 

 Terebratulina, D'Oibigny 

 Hynniphoria, Suess. 

 Terehratella, D'Orbigny 

 Megerlia, King . . 

 Megathyris, Bronn . 

 Cistella, Gray. . . 

 Trigonosemus, Konig 

 Kingena, Davidson . 

 Magas, Sowerby . . 

 lihynchora, Dalman. 

 Magasella, Dall . . 

 Laqueus, Dall. . 

 J Fre7tula,T>a,n . . 

 Bouchardia, Davidson 

 Platidia, Costa . . 

 Kraussina, Davidson 



Theciuiid^ . . . 

 Thecidium, Sowerby. 



StrixgocephalidjE. . . 

 Stringocephalus, Sandberger 



PEXTAMERIU.1S 



Pentamerus, Sowerby . . 

 Conchidium, Linn6 . 

 Stricklandia, Billings . . 



i I 



