SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 53 



PAGE 



North American continent in pre-Cambrian time, elevation of 252 



North Attleboro, fossils from 341 



North Weymouth, fossils from 281, 284 



Obolclla lindstromi, mentioned 264 



mobergi, mentioned 264, 290 



* vermilioncnsis, mentioned 300 



Obolella (Glypiias) favosa, mentioned 290 



Occipital segment defined 238 



Occular segment defined 238 



oclandicus, see Paradoxidcs. 



Olenellidse Lindstrom, reference to 236 



Moberg, reference to and included species 236 



Vogdes, reference to 236 



first use of term and reasons for its rejection 233 



Olenelloidcs Peach 345 



Beecher, in synonymy 345 



Moberg, in synonymy 345 



Peach, species referred to the genus listed 232 



a degenerate genus of the Mesonacid?e. 347 



delimitation of genus 248 



development of, shown in diagram 249 



development of thorax in 245 



mentioned 236 



segmentation of cephalon 238 



stratigraphic distribution tabulated 251 



Olenclloides armatus Peach 347, pi. 40, figs. 2 and 3 



Moberg, in synonymy 347 



compared with Elliptocephala asaphoides 346, 349 



Olenellus gilberti 346, 347 



Pcedeximias transitaiis 346, 350 



mentioned 342 



stratigraphic distribution tabulated 251 



Olenellus Hall 311 



Bernard, in synonymy 268, 312 



Cole, in synonymy 312 



Ford, in synonymy 261, 267, 311 



Hall, in synonymy 311 



Holm, in synonymy 261, 267, 286, 311 



Lindstrom, in synonymy 268, 312 



Marr on the telson of 313-314 



Marcou, in synonymy 311, 312 



Peach, in synonymy 312 



on the telson of 313 



Peach and Home, in synonymy 312 



Pompeckj, in synonymy 312 



Walcott, in synonymy 267, 274, 311, 3;^y, 338, 340 



Weller, in synonymy 312 



Whitfield on the telson of 313 



