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marl stage, consists of marls and shales, with isolated 
nummulites, many orbitoids, lamellibranchs, and crusta¬ 
ceans. The fourth, or limestone stage, which forms coral 
reefs, contains numerous fossils, among which are num¬ 
mulites and many orbitoids. These strata are broken 
through and disturbed by basalts, augite- and hornblende- 
andesites, which are associated with breccias, conglomerates, 
and tuffs of eruptive origin. The age of these rocks is 
probably Miocene, for the limestone stage is also pierced 
by them. As to the composition of the younger Tertiary 
formations little is known. They appear, however, to 
consist also of sandstone, marl, and limestone beds, and 
the limestones are said to occur as coral reefs.” 
The abundance and wide distribution of coal in the 
island is remarkable. In this respect Borneo is by far 
the richest of all the islands of the Malay Archipelago. 
Schwaner says :—“ The occurrence of coal is more wide¬ 
spread than one might be led to think by a first examina¬ 
tion. In the whole of the hill-formation it constitutes 
a most important and almost never-failing factor. All 
fissures and openings that have been made use of for the 
investigation of the underground geology have led to the 
discovery of coal seams, and even the banks of the great 
rivers disclose them in many places.” As far as is 
known, there is no coal of greater age than the Tertiary 
period. Most of it belongs to the Eocene, but the brown 
coals of the Miocene also occur plentifully. 
Mr. Motley, in his Report on the Geology of Labuan 
and neighbourhood, gives the following interesting de¬ 
scription of its peculiarities :—“ The coal, dense and 
perfectly carbonised as it is, yet exhibits most unequivo¬ 
cally its vegetable origin; and not only that, but even 
the kind of vegetation of which it has been composed is 
evident from the most cursory inspection of the heaps of 
