333 
Guppy Rp:print 
185 
the Caroni series as laid down by Wall and Sawkins in the Geo- 
logical Report on Trinidad, i860, pp. 43, 45. The strata under- 
Page 2 
lying the Shellbed pass downwards into fine-grained soft rocks 
characterized by the Foraminifer Planorhdhia larvata. This po- 
sition is correctly indicated in the Diagram at p. 30 of The Pro- 
ceedings of the Societ}' illustrating my Paper on Recent Geologi- 
cal Discoveries (Vol. XII., 1912). These strata are there indi- 
cated by the letter h3 and h2 (Page 9 of separate copies.) 
Interstratified with the mudbeds are strata of a more perme- 
able quality, con.sisting of fine sandstones, and these pass in places 
into gravel beds sometimes indurated and these sandy and gravel 
beds allow of the percolation and storage of water w’hence the 
springs which are common in this country. The lower portion 
of the Caroni Series especiall}’ contains gravel beds which seem 
to overlie the cretaceous rocks. In fact the gravelly and sandy 
beds of the Tertiaries are here chiefly derived from the cretaceous 
.series. I did not see the lower miocene beds (the Tamana Ser- 
ies) exposed anywhere in this locality, and it ispo.ssible that the}- 
may not have been developed here, or they may be in part or 
wholly repre.sented by the strata underlying the Shellbed. 
On one point it seems necessary to give a caution. That is. 
the diagrams attached to my papers are not intended in any way 
as finished plans or sections. Thus the diagram of the Orbitoides 
Bed {Proceedings, p. 20^') is intended only to show approximate- 
ly the position of that bed ; it is not drawn to scale nor is it in- 
tended to show the dip or the relations of the other beds. The 
diagram is sufficient for its purpose. The faults shown in the 
diagram of which it is a modified copy (Journ, Geol. Soc., 1892, 
Page 522) are not indicated. Again the diagram at Page 9 of 
my Paper on Recent Geological Discoveries, (page 30 of Proceed- 
ings') is purely diagrammatic^ It shows correctly the relations 
of the strata so far as yet ascertained. But these diagrams are 
merely generalized .sections, and for convenience the height 
Page 3 
is greatly exaggerated and no attempt is made to show 
