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Order BOTHRIOCIDAROIDA Jackson 

 Family Bothriocidaridae Klem 

 Bothriocidaris Eichwald . 



B. archaica sp. nov. 



B. pahleni Schmidt . 



B. globulus Eichwald. Genotype 

 Order CIDAROIDA Duncan 

 Family Cidaridae Gray 

 Miocidaris Doderlein 



M. keyserlingi (Geinitz) 



M. camioni sp. nov. 

 Order ECHINOCYSTOIDA nora. nov. 

 Family Palaeodiscidae Gregory . 

 Palaeodiscus Salter 



P. ferox Salter. Genotype 

 Family Echinocystidae Gregory . 

 Echinocystites Wyville Thomson 



E. pomum Wyville Thomson. Genotype 

 Order PERISCHOECHINOIDA M'Coy 

 Family Archaeocidaridae M'Coy 

 Eocidaris Desor 



E. laevispina (Sandberger) . Genot3rpe 

 Archaeocidaris M'Coy 



A. worthcni Hall 



A. legrandensis Miller and Gurley 



A. longispina Newberry . 



A. glabrispina (Phillips) . 



A. nerei (Miinster) . 



A. rossica (Buch) 



A. agassizi Hall 



A. illinoisensis Worthen and Miller 



A. coloradensis nom. nov. 



A. keokuk Hall 



A. gracilis Newberry 



A. aculeata Shumard and Swallow 



A. shumardana Hall 



A. edgarensis Worthen and Miller 



A. newberryi Hambach 



A. Irudifer White 



A. norwoodi Hall 



A. paradoxa (Eichwald) . 



A. mucronata Meek and Worthen 



A. dininnii White 



A . oralis White 



A. acanthifera Trail tschold 



A. pizzulana Gortani 



A. megastyla Shumard and Swallow 



A. biangulata Shumard and Swallow 



A. ornata (Eichwald) 



A. ourayensis Girty 



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