TEETIAET MTCROZOIC FOEMATIONS OE TRINIBAB. 531 



What further information I have gleaned shall be briefly stated 

 here. Por, although the object of this paper is more particularly 

 the microzoic marls of jS'aparima, I believe, from palseontological 

 and stratigraphical considerations, that there was no real break in 

 the series of deposits from the Cretaceous to the Eocene in the 

 Parian area. Oscillations of level there probably were, and move- 

 ments of the earth's crust appear to have been frequent ; but sea 

 prevailed in this region throughout the period and the fauna of the 

 Cretaceous is perhaps more intimately linked with the Eocene than 

 that of the latter is with the Miocene. 



In 1863 I contributed to the 'Geologist' (pp. 204 and 363) a 

 notice of some fossils that I had found at Pointapier. These included 

 a belemnite, a Trigonia, and some other inollusca considered to be 

 identical with species found in Lower Cretaceous rocks in South 

 America. I have lately been led to suspect that these fossils came 

 from a bed of shaly conglomerate in which the shaly material is 

 the matrix, while the fossils and pebbles are derived from a pre- 

 existing rock. 



On my last visit to this locality I found exposed a bed I had 

 never seen before. It is a very fine-grained material containing 

 small shells, of which the most abundant is a Ditrupa. There are 

 some pteropods and other mollusca. In the presence of water this 

 rock is the most incoherent of any I have ever met with. It falls 

 into powder at the mere contact of water, and for the most part 

 the fossils disintegrate likewise, so that there is a difficulty in 

 getting anything like perfect specimens. Careful washing brings 

 to light a considerable number of extremely minute foraminifera. 



A few foraminifera may be obtained of ordinary size, but large 

 specimens generally go to pieces. There then remain, the far 

 more numerous minute forms, together with spicules of Tethya, 

 Halichondria, Gorgonia^ &c., and amorphous particles. The most 

 abundant foraminifera in this rock (after Globigerina) are Bolivinoe 

 of many varieties and some Miliolinoe. Bolivince are rather rare 

 comparatively in the Naparima foraminiferal marls, and Miliolince 

 are not common in them. In the next portion of this paper I 

 give lists of the foraminifera from the Pointapier microzoic rock and 

 from the radiolarian marls. A thorough exploration of these rocks 

 will yield many more forms. Of \\iq few I have isolated some have 

 been left unnamed, including a Pulvinulina {P. canariensis possibly), 

 a Truncatulina, and a Rotalia. So far as revealed, the foraminiferal 

 fauna of the Bitrupa-hed resembles that of the radiolarian marls 

 of South JS'aparima in the characteristic Glohigerince, in the small 

 size of the generality of the species, and in the abundance of minute 

 Bolivince. On the other hand calcareous (Gorgonia) spicules are 

 rare or wanting in the radiolarian marls, and I have not detected 

 Miliolince in them. And, moreover, the last mentioned rocks are 

 distinguished by the abundance of radiolaria in them and by the 

 occurrence in large quantity of silicate of magnesia. 



