102 
the eoastal area generally ; and it seems impossible to correlate 
it with anything else in the Nantasket region. But in that case 
the conglomerate and the highly amygdaloidal melaphyr over- 
lying it must be referred to the very summit of the Nantasket 
seetion ; and this amygdaloidal melaphyr north of the fault-scarp 
їз thus widely separated in time from the very similar melaphyr 
south of the fault. This view also implies the recurrence at the 
top of the Nantasket section of the basic flows characterizing 
the middle portion of it. | 
According to the foregoing interpretations, the Rocky Neck 
section, as exposed to observation, is evidently far from com- 
plete or continuous; but the following list of the Nantasket 
strata will show more clearly than either the map or sections 
just what the deficiencies are :— 
Granite. 
l'irst conglomerate, basal. 
First melaphyr, compact and jaspery. 
Second conglomerate, highly jaspery. 
Porphyrite, wanting. 
Third conglomerate, wanting. 
Second melaphyr, wanting. 
Fourth conglomerate, wanting. 
Third melaphyr, amygdaloidal. 
Fifth conglomerate, normal puddingstone. 
Fourth melaphyr, compact and brecciated. 
Sixth conglomerate, ten feet. 
Fifth melaphyr, amygdaloidal. 
On referring to the map and sections (Figs. 12 and 13), it be- 
comes obvious that this great break in the middle of the series 
is due wholly to the east-west dike-fault, which, as previously 
explained, divides Rocky Neck into two areas having nothing 
in common so far as the stratigraphy is concerned. This im- 
portant displacement is quite clearly a continuation of that sep- 
arating Melaphyr Peninsula from West Porphyrite Hill and 
dividing the central and coastal areas, 
Sh tr 
