NO. I ABRUPT APPE.\RANCE OF THE CAMBRIAN FAUNA 1 5 



6. The apparently abrupt appearance of the Lower Cambrian 

 fauna is therefore to be explained by the absence on our present land 

 areas of the sediments, and hence the faunas of the Lipalian period. 

 This resulted from the continental area being above sea level during 

 the development of the unknown ancestry of the Cambrian fauna. 



I fully realize that the conclusions above outlined are based pri- 

 marily on the absence of a marine fauna in Algonkian rocks, but 

 until such is discovered I know of no more probable explanation of 

 the abrupt appearance of the Cambrian fauna than that I have 

 presented. 



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