HILL: GEOLOGY OF JAMAICA. 85 
Against the southern margin of the Cobre formation, as seen imme- 
diately back of the station in May Pen village ; it apparently occurs 
along interior margins of the plain between Old Harbor and Clarendon 
Park, known east and west of the Minho as Harris Savanna and Lime 
Savanna respectively, and is thus apparently deposited along a former 
Coastal margin which once here attinged against the low back coast up- 
lands through which the Bog Walk Canyon is cut, and previously shown 
to be composed of the Cobre formation. 
Stratigraphically the May Pen beds occupy a position immediately 
Preceding that of the ancient alluvial deposits elsewhere described as 
the Kingston. Fossils are numerous at May Pen, consisting entirely, so 
far as we observed, of indeterminate casts of Mollusca, being free from 
Corals, especially of the reef building species. Further study of this 
locality is very desirable. 
The Porus Formation. — From the crossing of the Cobre to beyond 
Porus there are in the railway cuts many fine exposures of a forma- 
tion resembling that at May Pen, consisting of loose, coarse textured 
Yellow clay marls accompanied by irregular lumps of limestone and 
Containing poor casts of fossils. Sufficient material was not obtained 
from it to determine with exactness its stratigraphic position, although 
lb is, in general, to the coastward of the Bog Walk limestone, and ap- 
Parently above it. The fossils which we have seen from it have facies 
More resembling those of the Bowden beds than of the later formations 
Presently to be described. 
There is also evidence that beds analogous to those of Bowden occur 
9n the south coast of Clarendon Parish at the foot of Round Mountain 
Near Bath, which, according to Sawkins,* contain fossils of the same 
Senera as those found at Bowden (Port Morant). A coral from this 
locality described by Duncan, and an Orbitulina by Jones, indicate fur- 
ther identity of the horizons. Unfortunately, the writer has not visited 
this locality. 
Of the beds described, only the Buff Bay and Bowden localities can 
bo Correlated with positiveness at present. The inclined position of 
the former shows that they partieipated in some of the later orogenic 
Movements of the island. 
; The final key to the Jamaican sequence depends upon the determina- 
tion of the upper relations of the Bowden and allied beds. That they 
Clearly overlie the greater mass of the white limestones I am most 
Positive, and are not at the base of all the white limestones, as asserted 
1 Jamaican Reports, p. 162. 
