243 
large overthrusts')*), the opinion being developed already, that 
these strongly folded and overthrust mountain chains surround the 
whole Banda-sea in the row of islands Timor—-Ceram—Boeroe, and 
that the row of islands: Soela islands—Obi—Misool on the outside, 
shows no overthrust-structure *). 
This opinion will appear to be supported by my explorations. 
Also in West-New-Guinea we found in the region south of the 
zulf of Mac Luer near the west coast an — as far as is known 
— rather normally folded tertiary limestone-marl-series in which 
accidentally occur layers and nodules of hornrock, and which 
already Hrirscur *) relates to have folding-axes approximately parallel 
to the coastline. This points to the fact that the limit between the 
overthrust mountain-chains and their ““Vorland”’ exists between both 
rows of islands mentioned above. This limit cannot orographically 
be followed, as is the case in the Alps, where e.g. the Säntis “in 
gleich zu Stein erstarrten Wellen eines hoch brandenden Meeres 
die grünenden Hügel des Appenzeller Landes iiberragt’’. However, 
my researches enable me to determine approximately the limit 
between the overthrust mountain chains greatly covered by the sea, 
and their “vorland”. 
As far as the row of islands from Timor to the east has been 
explored during the expedition of Prof. MorenNaraarr, the existence 
of large overthrusts unto the island of Babber*) bas already been 
accepted; I found strongly folded mesozoic deposits on the chief 
island Jamdena of the Tenimber group, and for several reasons | 
think it rather possible that the overthrust mountain cbains continue 
also over this group of islands. If this supposition proves to be true, 
the tertiary limestones of the island of Laibobar would occur on 
the inner side of this overthrust mesozoieum, and would e.g. be 
denudated in a “fenster”. 
The following facts seem to make this supposition probable. In 
1, J. WANNER. Geologie von West-Timor. Geologische Rundschau, Bd, IV 
1913, p. 145. 
2) G. A. F. MoLaNGRAAFF. Folded mountain chains, overthrust sheets and block- 
faulted mountains in the Kast-Indian Archipelago. Gompte Rendu du XlIme Congrès 
géologique internativual. ‘Teronto 1913. Ottawa 1915. 
3) G. A. F. MorrNeraars Verslag betreffende de wenschelijkheid van een weten- 
schappelijk onderzoek van de cilandenreeks tusschen Celebes en Nieuw-Guinea enz. 
Tijdschr. Kon. Ned. Aardr. Gen. 1914 no. 3, blz. 369 en vlg. 
4) H. Hrrscur. Reisen in N.W. Neu-Guinea. Geogr. Ethnogr. Ges. Zürich 1907/08, 
p. 76. 
5) F. A. H. WeoKHERLIN DE Marez Ovens. De geologie van het eiland Babber. 
Handelingen van het XlVe Nat. en Geneesk. Congres. 1913, p. 465. 
ron 
