Carboniferous Algal Deposits. 



U5 



The character of the water can hardly be determined 

 from the algae. These organisms at the present time 

 thrive in cold as well as in warm waters, illustrated by the 

 fact that in the cold waters of some localities of northern 

 Newfoundland Lithothamnium covers everything in the 

 shallows, and about the "coral reefs" it is one of the 

 most abundant organisms precipitating lime carbonate. 

 The algae do not even prove that the waters were salty, 



Fig. 2. 



Fig. 2. Collenia Tcona n. sp. Cross section of two colonies, Kona dolomite, 

 Marquette, Mich. The hammer is 18 inches long. Photograph by Dr. W. O. 

 Hotchkiss. 



as lime-precipitating algae thrive in both fresh and salt 

 waters, but the tremendous growth of the Kona algae sug- 

 gest marine conditions. 



The upper surface of the Kona reef was irregular from 

 the presence of elevations which are dome-shaped in cross 

 section. Some of these elevations appear to have been as 



