Outlines of the Bevniudas. — Fewkes. 91 
when we remember that an active modifying agent has exerted 
its influence in one case and not in the other. 
Buttlie evidences claimed to account for the outlines of the 
Bermudas do not rest wholly on their resemblance to those of 
compound atolls. It is held that we have in the Bermudas 
direct evidences of the subsidence of the base. This evidence, 
which is mainly derived from sunken Cedar trees and 
submerged cave stalagmites, will be considered presently. 
There seems evidence to lead to the belief that ring-shaped 
coral islands are not all formed in the same way. Prof. Heilprin 
strongly insists that the Florida reefs are on areas of eleva- 
tion to which I have no desire to object, but if one regards the 
Florida reefs as an area of elevation and an atoll as an indi- 
cation of subsidence how are we to explain the ring-shaped 
Marquesas' islands? Here certainly we have a ring-shaped 
coral-island in an area which the last mentioned author 
regards as one of elevation, but there is a danger in supposing 
that one ring-shaped coral island is necessarily formed the 
same as another of the same shape because its outlines are 
similar. My belief is that the outlinesof the Florida reefs are 
determined by ocean currents independent either of elevation 
or subsidence. There are illustrations which might be 
used to support the theory that circular reefs may not 
always be formed in the same way. I think possibly the Ber- 
mudas and the Marquesas are such examples. It is 
possible that some naturalists have found ring-shaped 
reefs in areas which they regard areas of elevation, 
others atolls in areas of subsidence, while still a third 
where there is no evidence of either elevation or subsidence. 
The causes which might theoretically lead to the formation of 
ring-shaped islands are certainly not so meagre that each, 
possibly all, may be right in regard to the islands which they 
have studied. 
The most important evidences of subsidence in the Bermu- 
das which have been advanced are : 1st. The finding of cedar 
trunks in upright position in submarine excavations, or depos- 
its of "peat" and redsoil in the same or similar excavations. 
To which may be added the fact that ships in Great Harbor, 
one of the sounds, have drawn up with their anchors frag- 
ments of cedar trunks and roots. 2nd. The existence, accord- 
