~, A somewhat crystalline light grey limestone, from mountain 
2,500 feet high. In appearance it somewhat resembles a coral 
- . limestone; none or but very obscure indications of organic sirue — 
_ture—not even on the external surface, which is much weathered. 
48° -——-—s- ROCKS FROM NEW BRITAIN AND NEW IRELAND. — 
Amongst the specimens are two rounded nodules of calcareous 
mudstone, containing some remains of branching corals, probably 
recent or li forms, but they are so much rolled that ther 
ool 
‘thin veins of epido 
_Sandstone.—Pale 
_ parallel layers, evidently planes of stratification. The dark pat 
de or augit? 
structure is very obscure. 
Pale brown calcareous mudstone, looks at first sight much like 
@ sandstone—contains much volcanic ash. as 
A difficulty in properly describing some of the specimens 8 — 
caused by the fact that they are merely small detached and rolled 
fragments. 
Ancient Volcanic ash.—Having the appearance of @ dark 
coloured conglomerate, hard and compact, made u of red, browly 
black and other pebbles embedded in a dark green felspathic en | 
which is porphyritic in parts, from the presence of dissemima® — 
white and grey crystals of felspar. 
Jasper pebbles.—One of a beautiful deep red .in pa 
| rt, with 
patches of white quartz. A cavity on one side is filled with 9 
porphyry made up of a dark green base with small disseminatl 
white felspar crystals. The porphyry resembles that of the ¢ i 
Yoleanic ash conglomerate, and is probably part of it 5 the jaspt 
pebble, however, does not look fused at all, but merely meee 
brownish grey, marked with thin rs 
are rendered so by the presence of small hornblen 
crystals, readily discernible under the microscope, being 00% . 
less transparent and of a green colour, but not with the unassist 
eye.. 
- Epidote a pebble apparently made up ofa felspar wit 
te, 
__ Decomposed Porphyry.—A red ferruginous pebble, a 
with an earthy fracture, darker mottlings in parts, an tall 
with a few white specks and very thin felspathic vems. 
a decomposed ferruginous igneous rock. fine 
Alluvial deposit, from the river. Brown in colour, Vey 
grain, pertorated with worm-burrows. ‘nterio® 
Another specimen is labelled stones and earth from the ‘poros 
of New Ireland, 2,500 feet. The earth is simply ap posed i 
clay-eoloured soil, but the stone looks like a much of & 
trachyte ; under the microscope it is seen to retain eye of 
crystalline structure, and green-coloured translucent oe 
what appear to be hornblende are abundant, : 
ais 
rd 
