322 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



At Bic Harbor on the St. Lawrence, C. senectus occurs in boulders 

 of light gray limestone associated with fragments of Oleuellns thorn p- 

 soni and the following species (locality 2 o) : 



Micromitra (Paterina) bella (Billings) 



Micromitra {Paterina) labradorica (Billings) 



Bicia gemma (Billings) 



Kutorgina cingulata (Billings) 



Obolella crassa (Hall) 



Botsfordia calata (Hall) 



Yorkia wanneri ? Walcott 



Nisusia festinata (Billings) 



Discinella sp. 



Corynexochus (Bonnia) parvulus (Billings) 



Corynexochus bubaris Walcott 



Zacanthoides spinosus Walcott ? 



Olenellus ihompsoni Hall 



At all three localities C. senectus occurs at the upper horizon of the 

 " Olenellus " or Lower Cambrian fauna, and in none of them is it 

 known to be immediately succeeded by the " Paradoxides " or Middle 

 Cambrian fauna. 



The species as identified from locality 6id in British Columbia is 

 represented by large numbers of the cranidium and associated py- 

 gydia that vary among themselves very much as the specimens from 

 western Newfoundland. The limestone matrix at the two localities 

 is nearly similar in color and appearance and the associated fauna is 

 very similar. The fauna listed in each instance is from the same 

 layer of limestone containing Corynexochus senectus. The horizon 

 of the layer at locality 6id is near the top of the Lower Cambrian 

 Mount Whyte formation, and at locality 41 1 in Newfoundland near 

 the summit of the Lower Cambrian {Olenellus) series. 



The fauna of locality 6id includes : 



Acrotreta sagittalis tacoiiica (Walcott) 



Nisusia (Jamcsella) lozvi Walcott 



Scenella varians Walcott 



Pelagiella sp. undt. 



Micromitra (Paterina) labradorica (Billings) 



Micromitra (Iphidella) paunula (White) 



Corynexochus senectus (Billings) 



Agraulos 



Zacanthoides 



Ptychoparia 2 spp. 



Mesonacis gilberti (Meek) 



