CAMBRIAN GEOLOGY AND PALEONTOLOGY 



II 



No. 7— CAMBRO-ORDOVICIAN BOUNDARY IN BRITISH 



COLUMBIA WITH DESCRIPTION OF FOSSILS' 



By CHARLES D. WALCOTT 



(With Plate 35) 



CONTENTS p^^^ 



Introduction 229 



Descriptions of species 



Obolus mollisoneiisis, new species 231 



Lingulella moosensis, new species 232 



Lingidella ? allani, new species 232 



Genus Ceratopyge Corda 233 



Ceratopygc canadensis, new species 233 



PLATE 35 



Figs. 1-6. Lingulella moosensis 236 



7-9. Lingulella ? allani 236 



10-12. Obolus niollisonensis 236 



13-22. Ceratopyge canadensis 237 



In a preliminary description of the Mount Bosworth Section of 

 British Columbia^ I placed the summit of the Upper Cambrian at 

 the top of the Sherbrooke formation, it being- stated that the highest 

 beds on the summit of Sherbrooke Ridge contained obscure fossils 

 that suggest Ophileta, also that the strata near the summit are 

 much broken up owing to a fault line that crosses the ridge. Dur- 

 ing the summer of 191 1 Mr. J. A. Allan, of the Geological Survey 

 of Canada, and Mr. L. D. Burling, of the LTnited States National 

 Museum, visited the locality on the summit of Sherbrooke Ridge and 

 found specimens of Lingulella isse (Walcott) and a species of 

 Ptychoparia in the upper beds, that correlates the upper limestones 

 with the Cambrian. 



^ Published with the permission of the Director of the Geological Survc}- of 

 Canada and the approval of Mr. John A. Allan. 

 ^ Smithsonian Misc. Coll., Vol. 53, No. 5, 1908. p. 204. 



Smithsonian Miscellaneous Collections, Vol. 57, No. 7 



229 



