It comprises a sinuous strip of territory measuring between 750 and 800 m.
It passes through the most picturesque scenery in Belgium and is remarkable for its sinuous course, its length of 120 m.
The south-eastern like the northwestern corner of the island is watered by a considerable number of short mountain streams. The one great river of the eastern versant is the Kutei or Mahakan, which, rising in the central mountains, flows east with a sinuous course and falls by numerous mouths into the Straits of Macassar.
In nearly all instances the rivers, owing to their sinuous course, are much longer.
It has been ascertained that the nephridia of Oligochaeta are preceded in the embryo by a pair of delicate and sinuous tubes, also found in the Hirudinea and Polychaeta, which are larval excretory organs.