146 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VoL. VIII. 
unlikely to be the case as those valleys follow lines of drainage which were 
traced out before the faultings and subsidences took place. 
As regards the question why the dislocations and faults should be 
regarded as due to subsidence rather than to elevation, I think the evidence 
is pretty clear that the Parian Range was upheaved however gradually 
as one mass as represented in Fig. 2. The forms of the submerged valleys 
show that they originated as sub-aerial valleys, consequently subsidence 
must have taken place, and to this subsidence are due the faults and dis- 
locations which occur throughout the formation. 
SUMMARY. 
The principal conclusions arrived at from a study of the geological 
phenomena exhibited in Trinidad are :— 
1. The land of which Trinidad formerly formed part, originated from 
deposits laid down in the sea and derived from pre-existing land. When 
this operation was going on the whole area occupied by Trinidad was sea. 
2. When the Parian Range rose above the waters it was the southern 
portion of a large continental mass of land whose extent we have not the 
means at hand to enable us to determine with any approach to exactitude. 
At this time the valleys of the Orinoko and Amazons were sea. 
3. During the neozoic or cretaceo-tertiary period, the rocks now form- 
ing the southern portions of the island of Trinidad were deposited; and 
were raised above the level of the sea towards the close of that period. 
During that time there was no separation of Trinidad from South America, 
and the land surface was continuous. It is probable that simultaneously 
with the rise of this land surface, extensive dislocations and depressions 
took place in the Caribean area resulting finally in the separation of Trini- 
dad from Venezuela, the formation of the Gulf of Paria, and the reduction 
by denudation of the newly-separated land to near its present level. The 
contemporaneous phenomena in other parts of the West Indies have been 
made the subject of discussion by J. W. Spencer, Gregory and others. 
