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I have also found a single valve of a deeply sulcated species of 

 Avicula. This is small, and the sulci, though deep, are not more 

 than five or six in number. It was probabl}' a young shell. 



Gasteropoda are represented among the fossils from Pointe a 

 Pierre ; but the specimens are generally so imperfect as to render 

 the determination of their relationships difficult. A cast in my 

 possession, upwards of two inches in length from the apex to the 

 peristome, seems to be of a naticoid type. Another cast which 

 has some shelty matter remaining on it may be either a Trochus 

 or a Pleurotomaria, probably the latter ; but the aperture is not 

 perfect enough for identification. 



All the fossils I have yet been able to obtain from Pointe a 

 Pierre have been from the beach. They seem to have been washed 

 out from the strata in which the3 T were originally deposited and 

 intermingled with the alluvium of a little hollow in which stand the 

 old works of the Bon Accord Estate. Tney are consequently much 

 worn; and it is hardly possible to ascertain from what portion of the 

 group they have been derived. Were quarries opened in the 

 adjoining hills this might be decided. The Trigo7iioe and Oysters 

 are tolerably well preserved as far as their structure goes, but 

 the shells of the Gasteropoda have nearly or entirely disappeared, 

 leaving only casts. The thick and massive character of the shells 

 is worth notice, and it prevails alike in all the specimens in w T hich 

 the shell is preserved. 



From what I have said, it will be seen that the evidence of the 

 age of the Older Parian formation is in favor of Mr. Etheridge's 

 view.* Until, however, more fossils can be obtained, and their 

 position in the formation better determined, it will be as well to 

 leave the precise age of the formation an open question. The 

 interest attaching to the point is not confined to Trinidad, as the 

 Older Parian is developed on the main land of South America, at 

 Cumana and other places ; and therefore it is to be hoped that 

 on further search more fossils will be discovered. 



The following is a list of the fossils found in the Older Parian 

 strata at Cumana and in Trinidad : — 



* Geological Snrvey of Trinidad, p. 162. 



