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Guppy Reprint 



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Page 179 



1872 part of the "Proceedings of the Scientific Association 

 Trinidad," and in the Geological Magazine (1873, p. 62), 

 I gave particulars to which I would refer for further eluci- 

 dation of the matter. I have only now to add with re- 

 ference to this part of the question that I have not been 

 able to explore that part of the coast section at Sanfernan- 

 do which lies between the portion shown in my diagram 

 in the Geological Society's Journal (previously referred to) 

 and the mouth of the Sipero River, 'and that I think it likely 

 that an exploration of that portion of the section would throw 

 some further light upon the relations of the Sanfernando beds 

 (Eocene) and the South Naparima marl (Miocene). 



In my paper published in the "Proceedings of the Scientific 

 Association of Trinidad" for December, 1877, I gave a diagram 

 (fig. 3) to show the general succession of the rocks of Trinidad. 

 In engraving this diagram the artist left out several of the letters 

 of reference, of which an explanation is given on page 115 of the 

 accompanying text. According to the diagram and the explana- 

 tion the rock formations of Trinidad are in ascending order as 

 follows: — 



(a bed) Caribean group (paleozoic). 



(e) Compact limestone ( Devonian) ? 



{/) Secondary rocks (Neocomian). 



(g) Eocene of Sanfernando. 

 (g / ) Eocene of Manzanilla. 



(h) Miocene of Guaracara. 



(k / ) Miocene of South Naparima (including the polycystina 

 marls. 



{h") Miocene of Savaneta, Point Noir, &c. 

 {h /// ) Miocene and Pliocene (mostly the latter, I believe), of 

 Moruga, Mayaro, &c. 



(i) Postpliocene. 



The letters omitted by the artist were g, h and h\ whiles' 

 was written as g. Had these errors not been committed, my 

 views as to the relative age of the rocks of Trinidad, including 

 the Eocene marls of Sanfernando and the Miocene marls of South 

 Naparima, would have been clear to any one referring to the dia- 

 gram quoted and its explanation. 



In December, 1888, and Januar} 7 , 1889, I corresponded with 

 Mr. Jukes- Browne, then in Barbados. Under date 8th January, 

 he asks me : "Is the P. marl at San F. iuterbedded with the 

 other beds ? If not and if the exposure is an isolated one, is it 

 not possible that the marl overlies the Eocene as it does here ? 

 In the absence of contained fossils (except Radiolaria) and in the 

 absence of direct evidence, it seems to me that the marl may be of 

 any age later than Eocene." I replied to this, sending Mr. 

 Jukes-Browne a copy of my diagram and explanation (fig. 3 and 



