Dr. Nugent on the Geology of the Island of Antigua . 471 
therein ; merely jasper in veins of the trap. My reason for con- 
sidering No. 1 to be of same formation with No. 2 is derived chiefly 
from the identity of the matrix, which is most peculiar, and the 
masses of trap being irregular, so that they cannot be reduced to any 
order or succession whatever. The more I think of it, and the 
more I examine, the more I am convinced this mountain-range is 
a conglomerate (not a mere breccia) on a great scale. It is im- 
possible to say what an original prolongation of this No. 1 beyond 
the present limits of the island might have afforded by detrition or 
debacle ; but from what we now see, it cannot be supposed to have 
afforded all the fragments included in the stratified conglomerate 
No. 2. The latter contains abundantly what cannot be found in 
No. 1 ; as silicified wood, coralline chert, agate, amygdaloid, 
porphyry slate, bloodstone, &c. The matrix of the conglomerate 
strata No. 2, though for the most part similar to that of No. 1, is 
frequently more compact, and of an intense green colour, from the 
greater impregnation or diffusion of green earth ; this green colour 
is never remarked in the matrix No. 1. I thought once that No. 3 
(chert) might have belonged to No. 2, but am now confident that 
it is subordinate to the inferior beds of No. 4. There cannot be a 
doubt of No. 2 being anterior to the marl No. 4 ; no geological 
point can be clearer, than that No. 4 is the latest of all the forma- 
tions here : besides, if No. 2 had been formed as an upfilling in the 
basin between No. 1 and 4, it would have contained some trace of 
calcareous rocks and substances, which is not the case, derived from 
one side as it derived trap fragments from the other. No. 2 like- 
wise never contains any chert with Cerithia, which almost entirely 
composes No. 3. There are no quarries, sections of which would 
illustrate the junction, nor could any make this part of the subject 
Vol. V. 3 o 
