108 
GEOLOGY. 
this sandstone becomes more silicious, and of a blackish blue 
colour, and is in some places flaggy, whilst in others the strati¬ 
fication is only indicated by the different colours of the deposits. 
All these rocks are intersected by joints. At the lowest visible 
part of these strata (at Maukurinui point), the sandstone is 
traversed by large quartz veins. It has been described by a 
former explorer as basalt, he mistaking the joints, coupled with 
the great dip of the strata, for a columnar structure. 
At this bold point, whilst climbing up the steep side of the 
cliff, I found impressions of fossil fishes in the rock, but as the 
native urged me not to lose a minute, the tide then flowing fast, 
and being likely to jam us for the night amongst these vertical 
cliffs, I was obliged, to my great annoyance, to leave the spot, 
which would, had I found time to secure some of these rare fossil 
remains, have thrown much light upon this interesting formation. 
It would be needless to give the strike and dip of all the strata, 
as they change very often, sometimes becoming almost vertical, 
and sometimes appearing to have been overthrown, but I shall 
give a general outline of them. 
At the Wai-a-whenua, south of the Maukurinui point, they 
strike from south-east to north-west, with a dip towards the 
south-west of 11 degrees, rising to 45 degrees near Kararoa. 
Hear the Maukurinui they strike north-east and south-west, with 
a dip of 53 degrees towards the north-west. Half a mile north of 
the last-named promontory the mountains recede, and I did not 
again obtain a section until near the Kokiwi, where I met with 
masses of dioritic porphyry protruding through the chain, which, 
with the lateral dislocation, accounts for all these disturbances. 
Half a mile east of the mouth of the Grey, we meet with a suc¬ 
cession of small limestone hills, which run nearly parallel with 
the coast, gradually approaching the sea, which they reach in the 
wild headland called Komatiki-tawhao. The strata in these hills, 
with a strike nearly north and south, and a dip of 35 degrees 
towards the west, exhibit all the characters of true upper cre¬ 
taceous rocks, although we do not meet with any deposits re¬ 
sembling chalk. 
Commencing in descending order, we first meet with flaggy 
beds, greensands, full of long rounded branching concretions, 
sometimes flattening towards the end, and often entangled with 
each other, and which without doubt are casts of fucoids (kelp). 
Besides Cardium and a Terebratula, I found a large Pecten and a 
Cyprina, and many Echinoderms, amongst which I collected a 
magnificent Cidaris, and several specimens allied to Spatangus and 
Toxaster. This greensand is underlaid by bluish grey chalk marls, 
250 feet thick, with bands of compact pale yellowish limestone, 
which, being harder than the chalk marl, has better resisted the 
action of the waves, and everywhere projects from the body of 
the rock. For the first 120 feet, in a descending order, these 
