INDEX 469 



PAGE 



Oesa Lake, British Columbia, generic name derived from 133 



Ocsia Walcott, new genus described 132 



compared with recent annelids i33 



genotype, Ocsia disjuncta I33 



geographic distribution 133 



stratigraphic range I33 



disjuncta Walcott, new species described 133 



figured, pi. 20, figs. 3-5 138 



compared with Nicomachc japoiiica 133 



stratigraphic position and association 153 



Ogygia, Dikelocephalus compared to, by Owen 365 



Ogygopsis klotsi (Rominger), associated with Mollisonia symmetrica. .. . 197 

 Ogygopsis shale, Stephen formation, British Columbia, Middle Cambrian 



locality 17-38 



Ogygopsis zone, Stephen formation, Sclkirkia found in 122 



reference to 42 



Oklahoma, Dikelocephalus in 359 



Upper Cambrian locality I2g in Arbuckle limestone 372 



Oleiielliis, from Robson Peak district 309 



fauna, discussed 2 



listed from Hota formation 335 



from Mahto sandstones 335 



mentioned under stratigraphic section 338 



relation to Olcnopsis 239 



significance of occurrence 13 



canadensis Walcott, absent from new Lower Cambrian sub-fauna.. 310 



compared with Wanneria occidcns 314 



listed in stratigraphic section 338 



gilberti Meek, compared with Olenellus trueniani 316 



compared with Wanneria occidens 314 



lapzvorthi Peach, compared with Olenellus tri4emani 316 



reticulatiis Peach, compared with Olenellus truemani 316 



thompsoni (Hall), associated with Olenopsis roddyi 240 



compared with Olenellus truemani 316 



truemani Walcott, new species described 316 



figured, pi. 54, figs. 2-10 326 



compared with Olenellus thompsoni, O. gilberti, O. reticiila- 

 tus, O. lapzvorthi, Pccdeumias transilans. and 



Wanneria halli 316 



listed in stratigraphic section 339 



zone, larger fauna to be obtained from 310 



sp. undt., listed in stratigraphic section 338 



Olenidae, Conocephalites (=: Conukcphalina) and grotip of forms to be 



considered in review of 348 



Oleninse, Crcpicephalus Owen related to 347 



Olenoides, listed in stratigraphic section ^7 



? cilix Walcott (=Blackzi'elderia cilix (Walcott)), former and 



present generic reference 71 



leblanci Bergeron (:= Blackz-vclderia sinensis (Bergeron)), former 



and present generic reference 71 



