GUl'PY — OLDER PARIAN POUMATIUN IN TBLNIDAD. 



205 



minatea rather abruptly before reaching the east coast, but the for- 

 mation reappears here and there near the south coast along a lino 

 parallel to the main band.* The formation is only exposed for a 

 short distance on the shores of the Gulf of Paria; but it has been 

 found to cover a large area, and to be extensively developed on the 

 continent of South America. The fossils found by the geologists in 

 Trinidad seem to have been few, and for the most part indetermin- 

 able. They however obtained fossils from the same formation at 

 Cumana, in Venezuela ; and these remains led to the belief that the 

 Older Parian was probably of Neocomian age. During a short visit to 

 Pointe a Pierre I obtained several fossils, which have enabled me to 

 make the observations detailed in the present paper. 



The section given by the Government geologists of the Older 

 Parian deposits at Pointe a Pierref is taken on the south side of the 

 point, which I have not had an' opportunity of examining carefully. 

 The geologists do not seem to be able to give much attention to that 

 portion of the deposits which is exposed on the north side of the 

 point, and I hope that the present paper, in so far at least as it relates 

 to the fossils, may in some measure supply the deficiency. 



The extreme point of the cliff at Pointe a Pierre is formed of a 

 hard ferruginous sandstone, which is somewhat brittle and coarse in 

 its structure, and contains no fossils. The dip is from 40° to 45° 

 south. The beach north of the point is passable at low water, and 

 consists of pieces of rocks more or less rounded, which have fallen 

 from the cliffs above. Going north along this beach, we find alter- 

 nations of sandstone of variable quality, with shales of a black colour 

 and thin unconsolidated layers of very fine sandy matter, some of 

 which are black and some nearly white. It is only, however, at the 

 north end of the beach that I have been able to detect organic re- 

 mains. The most conspicuous of these is a Trigonia, considered to 

 be the same species as that found at Bogota, and named by D'Orbigny 

 T. subcrenulata.% Of this fossil, I have found one entire specimen 

 and several disunited valves. 



Mr. Etheridge notices the entire absence of Cephalopoda in the 

 collection made by the geologists when there, stating that the want 

 of such fossils prevented a comparison with the strata at Bogota and 

 in other parts of South America. § I have obtained a specimen of 

 Behnniitcs from Pointe a Pierre, so very imperfect and worn how- 

 ever, that it is difficult to ascertain to what section of that genus of 

 Cephalopoda it belongs. If, however, it be] ngs, as is perhaps pro- 

 bable, to Brown's section Aca^li, it furnishes additional evidence of 

 the correctness of Mr. Etberidge's determination of the age of the 

 strata exhibited at Pointe a Pierre as Neocomian. The presence of 

 the Belemnite is at once a proof of the Meso/.oic age of the Older 

 Parian group ; and, as Belemnites are not found above the Chalk, 



* Report on the Geology of Trinidad, p. 8 I. 

 t Ibid., sheet uo. 2, fig. 2. % Ibid., p. 1G3. 



§ Ibid. See also Wall, " On the Geology of Venezuela and Trinidad," Quart. Jouru. 

 Geol. Soc. vol. xvi. p, t(')0 H 8*q, 



