246 ANNUAL EEPOET SMITHSONIAN INSTITUTION, 1915. 



There is much still to be learned by larger and more systematic 

 collections in the Cambrian of China, and the future student of the 

 Cambrian system in Asia should also consider carefully the Siberian 

 Cambrian. The field is a large one, and what we now know of it in- 

 dicates a rich reward to the individual who takes the time to thor- 

 oughly work out the formations and their contained faunas. 



THE GREAT MIDDLE CAMBRIAN FOSSIL QUARRY OF BRITISH 



COLUMBIA. 



Nature has a habit of placing some of her most attractive treas- 

 ures in places where it is difficult to locate and obtain them. Nearly 

 30 years ago rumors came of a wonderful find of glaciers, forests, 

 mountain peaks, lakes, and fossil beds along the line of the rugged 

 pass through wdiich the Canadian Pacific Hailway was building,^ 

 but it was only during the past four or five years, while making 

 researches in the Canadian Rockies, that it was my good fortune to 

 discover highly organized marine fossils deep in the Middle Cam- 

 brian formation. In these the minutest details of the internal struc- 

 ture are wonderfully preserved and reveal a great deal not before 

 known of the life history of that period. 



To secure as complete a series of the fossils as possible work has 

 been continued for several seasons. The great fossil quarry is 3,000 

 feet above Field and 8,000 feet above sea level on the southwestern 

 flank of Mount Wapta. The conditions were such that in order to 

 reach the finest fossils it was necessar}^ to blast the solid beds out to 

 a depth of 22 feet (pi. 8). 



Most of the Cambrian rocks of this quarry section were deposited 

 in waters teeming with marine invertebrate life.^ As far as now 

 known, this was before the day of fish or of any other vertebrate 

 animal; no land plants are loiown to have existed then, and even 

 marine vegetable life, except in the lowest forms, was unrepresented. 

 Other animals, however, lived in great profusion, and here and 

 there conditions Avere so favorable for their burial in the mud and 

 sand of the Cambrian sea that they were imbedded unbroken, and 

 throughout all the processes of rock making and mountain building 

 they have escaped destruction (pi. 9). 



One of these favorable places was at the quarry, where the most 

 readily destroyed organisms, like the jellyfish (pi. 11, figs. 1, 2), 

 have been exquisitely preserved ; and we have crustaceans of numer- 

 ous varieties (pis. 9, 10, 15), many of which preserve the most 

 delicate branchiae and appendages. One can hardly realize that these 

 were buried in the mud 15,000,000 to 20,000,000 years or more ago 

 and have remained undisturbed while several miles of thickness of 



1 Walcott, A Geologist's Paradise, Nat. Geog. Mag., June, 1911. 



2 Idem. 



