Notices of Memoirs — Prof. G. A. J. Cole — E. J. L. Guppy. 471 



XIII. — The Lateeite and Bauxite Zone of I!^orth-East Ieeland.^ 

 By Professor Gkenville A. J. Cole, F.G.S. 



THIS paper was merely explanatory of an exhibit of the types of 

 rock formed during the interval between the basaltic eruptions in 

 the north of Ireland in Eocene times. It was urged, in agreement 

 with the views of Richardson and Tate and Holden, that the red 

 lateritic zone represents basalt altered in situ even down to depths of 

 40 feet, the so-called ' volcanic bombs ' in the layer being residual 

 lumps of less altered basalt. Such a type of alteration is clearly 

 connected with the climatic conditions of Eocene times. Some of the 

 pisolitic iron-ore may have accumulated on the surface of the laterite 

 in pools formed during the rainy seasons. The pale bauxites are 

 derived from sporadic eruptions of rhyolite, and the bi-pyramidal 

 crystals of quartz in them prove this over a wide area. The thin 

 bauxitic layer, occurring as it does above the pisolitic iron-ore, may be 

 in part formed by wind-borne material. 



XIY. — On some Fossil Shells ekom Compaeo Road, Teinidad.* 

 By R. J. Lechmere Guppy. 



AMONG the fossils submitted to me for determination at different 

 times by Mr. E. H. Cunningham- Craig, E.G.S., lately Govern- 

 ment Geologist, was one collection of peculiar interest consisting of 

 fresh-water shells of genera and species not now found in Trinidad, 

 and forming a fauna completely distinct from any now existing here. 

 The locality given me was Compare Road. I furnished Mr. Craig 

 with the names of the shells and notes on them, but I think it as 

 well to put on record the names of these fossils. 



1. Hemisinus sulcatus, Conrad. 

 Amer. Journ. Conch., 1870. 



Conrad considers IT. tenellus to be a near ally of this shell. It is, 

 however, very closely akin to H. hieinctus, Reeve, an existing species 

 of South American rivers. Melania cingulata, Moricand (Journal de 

 Conch., 1860, pi. xii, fig. 6), and M. [Melanopsis) irasiliensis, Mor. 

 (ibid., pi. xii, fig. 7), are also very near, 



2. Leptoxis crenocarina, Moricand. 

 An inhabitant of Brazilian rivers. A remarkable and aberrant form 

 of Melania. 



3. Anodon hatesii, H. Woodward, 

 Ann. Mag. Nat. Hist., 1871-4 ser., vol. vii, p. 103, pi. v, fig. 10. 



There is no need to go to Asia for the nearest analogue of this 

 bivalve, which is related to the Attodon leotaudi of our rivers and 

 equally so to A. sirionos, Orb., and A. puelchana, Orb., of South 

 America. The African shell figured under the name of Margaritana 

 pfeifferiana by Bernardi (Journal de Conch., 1860, pi. xii, figs, 1, 2) 

 bears much likeness to the species named, which are all closely related. 



' Eead before the British Association, Section C (Geology), Dublin, Sept. 1908. 

 2 Bulletin Botanical Department, Trinidad, July, 1908, Article No. 1005. 



