140 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VoL. VIII. 
small and short. With few exceptions the valleys run north and south 
or nearly at right angles to the general direction of the range. The 
valleys running to the southward are larger. Many of them are ditch- 
like and steep-sided in their lower or southern portions, while they have 
large lake-like expansions in their upper parts. This latter feature is 
indeed not less noticeable in those valleys which like Diegomartin, are 
broad and flat in their lower portions, than in those which, like Caura, are 
steep-sided, ditch-like ravines. This can be seen from an inspection of 
the map accompanying the Geological Report. I append a map showing 
this feature and also the dislocations which are the cause of it. I proceed 
to describe the phenomena. 
Fes. 9. Miocene 
The dislocations indicated in the diagram-sections (Figs. 3 and 4), 
and in the map (Fig. 9) which traverse the range from west to east, no 
doubt took place at various times in the geological history of Trinidad. 
Which was the oldest of these dislocations is hard to determine but it may 
possibly have been the most southerly of them. This passes through 
Latinta Bay, Chacachacare, giving its direction to Chacachacare Harbour, 
a sunken valley formed along the line of that fault. This same fault 
passes north of Gaspari and Puntagorda, and continues its easterly course 
near the base of the southern slopes of the higher hills. The next great 
dislocation north of this, is marked by the saddle between Santacruz and 
Maraval, by the Maracas Waterfall and by several escarpments throughout 
the range. This is the dislocation which has had the principal share in pro- 
ducing the lake or basin-like expansions of the valleys in their upper parts 
described in this paper. Another line of dislocation is marked by Makarip 
Cove, and this also continues eastward through the range at a distance 
from one to two miles north of the one last mentioned. The northern 
Fug- te. Post plioce ne 
escarpment of Tucuche, among others, is due to this fault. Most, or more 
probably all, the east and west valleys which occur in the range are in one 
or another of these dislocations. 
