species, the gibbon (HYLOBATES MULLERI) is closely allied to species
found in the mainland and in Sumatra, while the MAIAS or orang-utan
(SIMIA SALYRUS) is found also in Sumatra and, though not now surviving
on the continent, must be regarded as related to anthropoids whose
fossil remains have been discovered there.[2]

The zoological evidence thus indicates a recent separation of Borneo
and Sumatra from the continent, and a still more recent separation
between the two islands.

The climate of the whole island is warm and moist and very equable. The
rainfall is copious at all times of the year, but is rather heavier
during the prevalence of the north-east monsoon in the months from
October to February, and least during the months of April and May. At
Kuching, during the last thirty years, the average yearly rainfall
has been 160 inches, the maximum 225, and the minimum 102 inches;
the maximum monthly fall recorded was 69 inches, and the minimum
.66, and the greatest rainfall recorded
in one day was 15 inches. The temperature hardly, if ever, reaches
100[degree] F.; it ranges normally between 70[degree] and 90[degree]
F.; the highest reading of one year (1906) at Kuching was 94[degree],
the lowest 69[degree]. Snow and frost are unknown, except occasionally
on the summits of the highest mountains. Thunder-storms are frequent
and severe, but wind-storms are not commonly of any great violence.

The abundant rainfall maintains a copious flow of water down the many
rivers at all times of the year; but the rivers are liable to rise
rapidly many feet above their normal level during days of exceptionally
heavy rain. In their lower reaches, where they traverse the alluvial
plains and swamps, the rivers wind slowly to the sea with many great