NORTH SCOTLAND 565 



Of these, numbers 1 and 3 have been obtained from the Beekmantown 

 of Newfoundland (1 from zones P-M and 3 from zones G-H of Billings), 

 while number 4 was originally described from the Lower Beekmantown 

 (Eomaine) of the Mingan Islands. 



It is thus evident that the lowest fossiliferous beds succeeding the indi- 

 cated break in the series have a typical Beekmantown fauna, and although 

 these and the succeeding members of the Durness limestone series are 

 classed as Middle and Upper Cambric by British geologists, it is clear 

 that they belong in the base of the Ordovicic, and that Middle and Upper 

 Cambric are wanting here. The conditions arc thus the same as those 

 found in western Newfoundland and in the Saint Lawrence Valley, as 

 well as in the region east of Lake Champlain, where Lower Ordovicic 

 beds follow on Lower Cambric. Moreover, it is evident that the faunal 

 characteristics of the Durness series ally it with the Beekmantown lime- 

 stones of western Newfoundland rather than with those of any other 

 British or continental formation. The close correspondence between the 

 North Scottish and American deposits, expressed even more strongly in 

 the succeeding members of the Durness group, was pointed out as early 

 as 1859 by Salter, and has been recognized by every one since. Yet these 

 beds have always been referred to the Cambric by British geologists, even 

 though some of the fossils found in the higher beds are of Black Eiver 

 types. 



No fossils have been found in the Sangomore dolomites, but the Bal- 

 nakiel and Croisaphuill groups contain a considerable assemblage of 

 organisms, all of which I had the opportunity of studying in the collec- 

 tions of the Edinburgh Museum through the courtesy of the custodians. 

 The specifically identified forms are given in the following: 



