466 Dr, Nugent on the Geology of the Island of Antigua* 
these beds of flint belong to the calcareous formation, or to that 
which is subjacent, or even whether they are not more recent than 
all ; but an examination of the church and Bayer Otto’s hills, Rat 
Island, and a spot at Murray’s, together with the fossil remains, 
decide the point satisfactorily to my mind, in favour of their belong- 
ing to the superior formation. 
Beneath these beds of marl and chert is found an extensive series 
of very peculiar stratified rocks, reaching all across the island from 
the ridge and Willoughby Bay, to the neighbourhood of St. John’s. 
I have never before met with any class of rocks of this nature, and 
shall venture to call them the claystone conglomerate. The 
numerous strata of which it is composed, though evidently belonging 
to one family, are often so different in their individual appearance, 
as to render it no easy matter to convey an accurate idea of them. 
The general outward character of the hills which are composed 
of these rocks, is a precipitous cliff on one side, and a gradual slope 
on the ether, as may be noticed at Monk’s Hill, and the neighbour- 
ing heights. Viewed in a hand specimen, this rock would for the 
most part be taken for a clay porphyry : but on farther enquiry, it 
possesses neither the habits (if one may say so) nor the geognostic 
relations of a porphyry ; it is distinctly stratified, and the strata are 
different from one another; they vary extremely in colour, external 
character, and thickness, (from a few inches to many feet) but all 
dip at a considerable angle to the north-west. The more usual 
composition of this rock is a clayey basis, with minute crystals of 
felspar, and numerous spots of griinerde or chlorite baldoge, which 
is either of a lively green, or of an olive or brown hue. The latter 
mineral gives the rock a most distinguishing feature, and, being 
frequently diffused through it, also a remarkable green tinge, as 
may be seen more particularly at the fortifications at Monk’s hill, 
