INDEX 451 



PAGE 



Eoortliis, new genus 102 



classification of 142, 148 



compared with Billingsella 104 



Orthis 104 



Plectorthis 104 



evolution of pi. 11 (pp. 140-141) 



coloradoensis, stratigraphic position and association. .. 173, 175, iQi, 192 

 coloradoensis as used in this hook^^ Eoorthis desiiiopleura. 



Jiastingsensis (Walcott), mentioned 104 



neivberryi, new species 105, pi. 10, figs. 6 and 6a 



compared with Eoorthis ronnlcha 105 



Eoorthis seno 106 



stratigraphic position and association 192 



remnicha, compared with Eoorthis neivberryi 105 



stratigraphic position and association 180 



thin section of 164, pi. 12, fig. 3 



remnicha winiieldensis, compared with Eoorthis zeno 106 



thyone, new species 105, pi. 10, figs. 7 and ya 



compared with Eoorthis zvichitensis 105 



stratigraphic position and association 180 



zvichitensis, compared with Eoorthis thyone 105 



mentioned 104 



seno, new species 106, pi. 10, fig. 8 



compared with Eoorthis neivberryi 106 



Eoorthis remnicha zviniieldensis 106 



stratigraphic position and association 196 



Eophyton sandstone, Sweden, fossils in 55 



Eostrophomena, classification of 142, 148 



evolution of pi. 11 (pp. 140-141) 



Ephebic, defined 156 



erecta, see Nisusia (Jamesella). 

 escasoni, see Obolus (Westonia). 



Esmeralda, fossils from 330 



Essex County, New York, fossils in 72 



Esthonia, Russia, fossils from 263 



thin section of fossil from 151 



Esthonia formation, mentioned 263 



Etheridge, R., Jr., bibliographic reference 112 



species named after no 



etheridgei, see Hiienella. 



Ethmophyllum gracile, stratigraphic position and association 187 



euglyphus, see Obolus {Westonia). 



Euobolus Mickwitz, compared with Obolus (Mickzuntzclla) and Scluiiidtia. 70 



Eureka District, fossils from 285, s--> 3^3^ 345 



Pioche formation in 12 



Eureka District section, Nevada, new formation names proposed for 184 



excelsis, see Trematoholus. 

 exporecta, see Billingsella. 



