120 Transactions. 
The strueture of New Britain has recently been summarized by Reed 
(1921) and Stanley (1923, 1924). On the inner northern side of the 
arcuate island the sea reaches a depth of 1.400 fathoms, but on the 
and syenite, gabbroid rocks, with diabases and porphyrites. These are 
associated with oo (?) grey-white limestone containing Acteonella, 
possibly, however, to be correlated with that occurring on the Purari 
River (Papua), and Ga crystalline limestones in New Ireland and the 
Solomon Islands. There are also steeply dipping older Miocene sediments, 
overlain unconformably by gently folded Pliocene series of foraminiferal 
sediments and tuffs. The volcanic eruptions seem to fall into three chief 
epochs, the first dating back to the close of Miocene time. These periods 
the adjacent archipelago. Stanley (1924) remarks: “ The first phases 
were associated with the main tectonié zones of faulting, which were 
more or less parallel to the axis of folding. The second phase was 
conterminous with subsequent strand-folding, which I consider represented 
the maximum period of movement in late Tertiary times. The third or 
set; but these later агаа аге due ол to a second set о 
fractures—namely, a series of north-and-south rifts, more or less at right 
angles to the coast-line, which are well in evidence throughout New 
Britain, and to a lesser extent in the islands of the D'Entrecasteaux 
Group." An especially good example of this is seen in the Willaumez 
Peninsula, projecting northwards from the centre of New Britain. The 
modern volcanic activity is thus greatest along the north coast of this 
island, and, as has been noted, it extends thence in an arc westwards to 
the Dampier rai Schouten Islands along the north coast of New Guinea. 
To the north-east the strike swings round into — opas with that of 
New Ireland, which runs from north-west to south- 
In New Irland; according to Schubert's Piet cited by Stanley 
(1923), together with those of Sapper and Lauterbach (1910), there is 
asement series of gneiss and grey crystalline limestone invaded by 
plutonie rocks ranging in acidity from granites to gabbros.  Diorites are 
so found in the islands in St. George's Channel between New Britain 
and New аи; and іп New Hanover to the north-west of the latter. 
They are overlain by older драчы rocks, Miocene-Pliocene foraminiferal 
limestone, &c., and raised coral-limestones, with abundant Recent 
volcanic rocks. The presence oie of an old folded cordillera is quite ` 
clear, and it may be traced from the Admiralty Islands, where ancient 
rocks have been found beneath" modern volcanic accumulations (fide 
Stanley), through New Hanover and New lreland, in which the strike 
bends sharply from south-east to due south. This geanticline appears 
to have subsided for three hundred miles thence to the south-east, but 
- Жул pores of аа major structure termed ‘ ‘the first Australian 
by The innermost or western member of the three is that 
wes has add been Ey sce the central member runs through the 
