192 TRANSACTIONS OF THE [APR. 16, 
several small patches, only a few yards in extent and fading out 
into the unaltered massive rock. Over considerably larger 
areas, as at Sandy Point in the northern strip, and on the Sandy 
Point road in the southern, the rock is much shattered by 
jointing, and somewhat crushed, so that its structure is not 
easily seen in the hand specimens, In several places along the 
edges of faults there is a considerable amount of breccia, con- 
sisting of rounded quartz grains ina fine green paste. But in 
general the intrusion is little affected, except for the develop- 
ment of secondary minerals mentioned above. Uralite and epi- 
dote are present in all the sections. 
Contact EFFECTS. The edge of the intrusion, where not hidden 
by surface deposits, is usually faulted. The actual contact can 
be seen only at two localities on the southern band: one just to 
the east of the river St. John, on the south side of the mass; the 
other west of the river, on the north side. 
The first mentioned contact is with a mass of olivine-gabbro 
which will be described later on. Here the junction can be 
plainly seen on the bare rocks on which the suburb of Indian- 
town is built. It forms a jagged, irregular line, the quartz- 
diorite sending out small dikes and stringers into the gabbro, 
and a large tongue along its eastern edge. Numerous included 
blocks, up to a ‘foot in diameter, are seen near the edge in the 
later rock. The gabbro near the edge is changed to a rock 
composed of more or less granular hornblende, with a greater 
or smaller amount of plagioclase. Receding from the granite, 
this hornblende is more uralitic, and the various stages between 
it and the scarcely altered gabbro can be traced. At a distance 
of one hundred feet there is very little change. The quartz- 
diorite near the contact is likewise altered ; ‘it becomes very 
fine grained and entirely allotriomorphic, composed of an 
evenly granular mixture of plagioclase, quartz and orthoclase, 
with small irregular grains and shreds of hornblende and biotite. 
No trace of porphyritic structure can be seen even in the small 
dykes. Several veins of coarse feldspathic pegmatite are seen 
cutting indifferently through both gabbro and quartz-diorite, 
their straightness and clean cut walls distinguishing them 
sharply from the true dykes, aside from the character of the 
filling. 
The larger offshoot mentioned is somewhat differentiated from 
the main mass, being uniformly darker, finer grained and with 
fewer and smaller phenocrysts. It contains about ten per cent. 
less silica. Its contact with the coarser rock is rather peculiar, 
suggesting the effect produced by stirring two thick liquids to- 
gether, and showing the strong disinclination of the two magmas 
