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HUBBARD AND CRONEIS 
fractures developed in the competent limestones during the time 
of folding. That it is younger than the chert, is often shown in 
specimens where the chert, as well as the limestone, has been 
cut by a calcite vein. Hence some of it must be very recent. 
The age of the iron ores has been discussed, but it may be added 
that they sometimes seem to be both secondary and primary. 
In conclusion, it should be said that this paper has but merely 
touched upon the geology of Giles County. Scores of problems 
stand out boldly bidding for solution, while many others lie half 
concealed and shyly invite attention. Not the least of the prob- 
lems available are those connected with the ancient life. In this 
area, the fauna is different from the fauna in the next county to 
the south. The comparison of the development of contempor- 
aneous life in isolated basins, which are yet not far distant from 
each other, may go a long way in the solving of some of the 
problems of evolution. When this work is at last undertaken, 
the area about Giles County will be a geologist’s “happy hunting 
ground.” 
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