Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/581

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They consisted of fourteen very large vertebrae of very slightly procoelian character (with processes in perfect preservation), bones of the pelvis and extremities, and a most singular one shaped like the ischium of a Plesiosaurus found in the other ravine, but much more angular. Here also a small hard concretionary boulder, as brilliant when fractured as fine granite, contained a very beautiful Steneopteris.

The whole collection, being brought safely to Christchurch, was forwarded to England in the ' Matoaka,' which sailed in May last, but has not since been heard of.

Discussion.

Mr. Boyd Dawkins remarked on the presence of Crocodilia in New Zealand being proved by the procoelian vertebrae.

4. On the Discovery of Organic Remains in the Caribbean Series of Trinidad. By R. J. Lechmere Guppy, Esq., F.L.S., F.G.S., President of the Scientific Association of Trinidad, &c. &c.

[Abstract.]

The author described the formation called the " Caribbean Group " by the Government Geological Surveyors of the West Indies as forming a considerable portion of the littoral cordillera of Venezuela, and as extending eastward through the north of Trinidad to Tobago. It consists of gneiss, gneissose, talcose, and micaceous slates, and compact limestones. The metamorphic rocks of Guiana lately described by Mr. Ralph Tate (Quart. Journ. Geol. Soc. vol. xxv. p. 343) are regarded by him as of the same age as those of the littoral chain of Venezuela; and it is probable that the series occurs again in New Granada. Mr. David Forbes mentions the occurrence of gneissic and metamorphic strata on the Bolivian coast and in the desert of Atacama. According to M. Pissis, an extensive series of micaceous and gneissoid strata underlies the Silurian beds of Illimani in Bolivia ; and Mr. Darwin alludes to strata of clay-slate &c. older than the Silurians of the Chilian Andes. The author considered that the Caribbean formation will be found to mark one of the " stable areas " insisted upon by Prof. Dana.

The northern range of mountains of Trinidad is composed entirely of rocks belonging to the Caribbean formation. The section from N.N.W. to S.S.E. from the sea, through the valleys of Diego Martin, Maraval, and St. Ann, shows the following succession of rocks in ascending order : —

1. Mica-slates, with quartzose sandstone ; 2. Crystalline limestone ; 3. Argillaceous slates, with hard sandstones, conglomerates, and thin beds and strings of calcareous matter; 4. Compact limestone, forming the Laventille hills bordering the plain of Caroni.

The total thickness of these rocks in Trinidad is stated by the author at upwards of 10,000 feet ; and he is of opinion that the thick-