38 S. F. Peckham—Pitch Lake of Trinidad. 
of Trinidad, and incidentally of the Pitch Lake, during the 
last thirty-five years. In 1860 Messrs. Wall and Sawkins pub- 
lished quite an extended report upon the geology of Trinidad, 
including observations upon the occurrence of bitumen 
throughout the island.* | 
Dr. Nugent remarked in the article above quoted, “and it 
must be remembered that geological enquiries are not con- 
ducted here with that facility with which they are in some 
other parts of the world; the soil is almost universally covered 
with the thickest and most luxuriant vegetation, and the 
stranger is soon exhausted and overcome by the scorching rays 
of the vertical sun.” + These observations exactly express the 
conditions under which these gentlemen performed their 
undertaking. It is therefore not surprising that errors should 
have been found in their conclusions and corrected by later 
observers. 
Mr. J. R. Lechmere Guppy, in 1892, thus stated the conelu- 
sions that he had reached in reference to Trinidad Geology.t 
“It appears from the evidence derived from the nature of 
the Naparima rocks, their fossil contents, and the movements 
which have effected them and the other formations of Trini- 
dad, that during the Cretaceous and Eocene periods, there was 
a sea having a considerable but variable depth of water, say 
up to one thousand fathoms and more. It is probable that this 
sea extended on the North to the base of the northern range 
of hills, a distance of some twenty or twenty-five miles from 
the northern limit of the Naparima deposits. During the 
Cretaceo-Eocene period the northern mountains probably 
formed an unbroken chain with the littoral cordillera of Ven- 
ezuela. This chain may be e¢ alled the ‘Parian Range.’ 
According to abundantly clear evidence given by me in 1877,§ 
the great chasms between Trinidad and Venezuela called the 
- Boeas del Drago were produced by subsidence. Previous to 
this the ‘Parian Range’ probably formed the southern boun- 
* Report on the Geology of Trinidad, by order of the Lords Commissioners of 
Her Majesty’s Treasury, London, 1860. 
+ Loc. cit., p. 70. 
¢ Quar, Journal Geological Soc., 1892, xlviii, 519-536. Ditto, xxii, 571; ditto, 
xxiv, 11; ditto xxvi, 413; ditto, xlviii, 221. 
The ‘‘Naparima rocks” consist of an anticlieal that abutting in a bluff near 
San Fernando, on the Gulf of Paria, extends across the island almost to the East 
coast. They also appear on the mainland of Venezuela near tho Bay of Cumana. 
The lowest strata are Cretaceous and are called together with the Kocene above 
them the ‘‘Older Parian.” The ‘‘ Newer Parian” above is Miocene and con- 
tains lignites and bitumen. Here orbitoides and nummulites are found in a mass 
of rock projecting into the Gulf of Paria, supposed to be Miocene. In the West- 
ern Hemisphere orbitoides are supposed to characterize the HKocene. In the 
Eastern Hemisphere nummulites are characteristic of the same formation. The 
deposit that here contains them both lies between other Miocene deposits. 
S Proceed. Scien. Assoc., Trinidad, Dec., 1877, p. 103. 
