46 P. T. CLEVE, 



found by Schombuegk and described by Fokbes, namely: Scalaria Ehrenbergii, Nucula 

 Schomburgkii and Nucula Pacheri. The geological age of this formation is not known but 

 it seenis most likely that it is of the eocene or cretaceous period. 



Of a newer ti me is the large formation of white and almost horizontal strata of 

 limestone with corals and shells, by which the southern, western and northern parts of 

 the island are covered, and which ascends from the sea in the form of four or five terraces. 

 This formation contains a large number of shells, of which a list is given by Schomburgk. 

 Most of them belong to species still living in the surrounding sea. Mr. Hovey*) remarks 

 that, out of 41, species of fossil shells collected by him, he could not find more than three 

 which he was unable to identify with living species, for which reason the formation appears 

 probably to belong to the latest pliocene time. 



That under this formation miocene beds occur is very likely as Mr Duncan**) de- 

 scribes a fossil coral, the Astrcea Barbadensis, as having been found in a well sunk 40 

 feet in the coral uiarl. This coral is also found in the miocene formation of Antigua. 



Trinidad***). In geological respect this island is a continuation of the geological 

 formations on the northern coast of South America. In the northern part of Trinidad 

 metamorphic rocks without fossils and of unknown age occur. They consist of micaceous 

 slates, sandstones and shales with bands of white or blue crystaline limestone. This series 

 of rocks is called by the British surveyors The »Caribbean». In the rniddle of Trinidad a 

 range of indurated sandstone with dark micaceous shales in exposed, and is believed 

 to belong to the lower cretaceous formation (Neocomian). This series is called the »Older 

 Parian». The space between the Caribbean and theolder Parian is filled with cry- 

 staline limestones and calcarious sands containing fossils and called the Tamana series, 

 which is overlaid ty the Caroni series of sand, shale, clay and calcarious sand, with 

 lignite. Near the crystaline rocks these beds are covered by a mäss of detritus from 

 the Caribbean rocks, which is termed the Detrital series. South of the older Parian are 

 the Sm Fernando beds, consisting of marl and indurated limestone, and to the south 

 of the latter series occurs the Moruga series. The S:n Fernando beds and the Ta- 

 mana series constitute together the lower, and the Caroni and Moruga series the upper 

 part of the Newer Parian, in the latter of which the mud-volcanos and the asphalt lake 

 occur. The newer Parian is supposed to belong to the miocene formation, but, judging 

 from its fossils, it seems more probable that the lower part belongs to the eocene and 

 only the upper part to the miocene formation. 



The fossils found in the San Fernando beds are: three species of Terebratula, several 

 species of Orbitoides, Ludna, Cardita, Pinna, Area etc, and beside these also the Echino- 

 lampas ovum serpentis Guppy and Hanina porifera Wood, the former and also a species of 



*) Sill. Am. Journ. Vol. XXXV, pag. 79. 1839. 

 **) Quart. Journ. Geol. Soc. Vol. XIX, p. 452. 

 ***) Litterature known by the autlior. 



1811 Nugent. Träns, of the Geol. Soc. L. Vol. I, p. 63. 

 1856 Bowen. Quart. Journ. Geol. Soc. Vol. XII, p. 389. 



1860 Wall, G. P. Om the geology of a part of Venezuela and of Trinidad. Quart. Journ. Geol. Soc. 

 Vol. XVI, p. 460. 



1866 Guppy. Quart. Journ. Geol. Soc. Vol. XVII, p. 570. 



