218 MK. JUZES-BROWNE AND PEOF. HAERISON 



In 1866 Mr. Lechmere Guppy described tlie coast-section at San 

 Fernando ^ as consisting chiefly of asphaltic clays, shales, and marls 

 inclined at a high angle to the south ; he regards them as belonging 

 to the same group as the Tamana and Manzanilla Beds on the north 

 of the Cretaceous ' divide,' referring them all on general grounds to 

 the Lower Miocene, and regarding the Caroni and Moruga Series as 

 Upper Miocene. 



In a later paper Mr. Guppy writes : — " The late discoveries (of 

 bitumen, &c.) added to my own observations make it seem probable 

 that the Nariva Series of the Government geologists is the equi- 

 valent, on the south side of tbe central range, of the Caroni car- 

 bonaceous series on the north." ^ This paper is accompanied by a 

 diagram to show the general succession of the Trinidad strata, in 

 which the Tamana and San Fernando Beds are referred to the 

 Eocene, the Caroni, Nariva, and JSTaparima Beds to the Miocene, and 

 the Moruga Series to the Pliocene. He does not, however, specially 

 deal with the relations of the JN'aparima Marls, and on our applying 

 to him in 1889 he was unable to give us any further information 

 about them, except that they are not exposed in the coast-section 

 at San Fernando. 



Prior to this, one of us had been over part of the Naparima 

 district and had seen the white radiolarian marls exposed in road- 

 cuttings. They appeared to succeed and overlie a great series of 

 clays and sandstones which much resembled the Scotland rocks of 

 Barbados, and as the dip of the marls in the sections seen was very 

 slight, and much less than that of the clays and sandstones, we con- 

 clude that the former rest unconformably upon the latter. More 

 recently our friend Mr. G. F. Franks, F.G.S., visited the same 

 district and obtained for us samples of the marls from several 

 localities ; he also is of opinion that they rest unconformably on the 

 older deposits, though whether these belong to the Nariva Series or 

 to the San Fernando Beds he could not ascertain. 



"We think, therefore, that the line between the so-called Miocene 

 and Pliocene of Trinidad will in all probability have to be drawn at 

 the base of the N"aparima JVJarls, and that when the real succession 

 and the exact relative age of the Trinidad Tertiaries are ascertained 

 the age of the Oceanic Deposits of Barbados will thereby be de- 

 termined.^ 



Examination of the samples obtained from the Naparima district 

 showed them to be similar in every respect to the Barbados earths. 

 Analysis proved some to be mainly siliceous, with only 30 per cent., 

 while others are calcareo-siliceous, with 40 per cent, of calcium 

 carbonate. Slides prepared from them showed that these earths 

 contain radiolaria and diatoms in abundance, the number of the 

 latter being greater than is usual in the Barbadian earths. 



^ Quart. Journ. Geol. Soc. vol. xxii. p. 571. 



2 Proc. Sclent. Aasoc. Trinidad, 1877, part xi. p. 113. 



^ The discovery of Nucida Schomhirgki in the San Fernando Beds by Mr, 

 Guppy naturally suggested the probability of their being of the same age as the 

 Scotland rocks of Barbados. He therefore refers the latter to the Eocene. 



