613 
ground-mass of limestone. The limestone N°. 286. 1907 rich in 
quartz-splinters bears half-sized Nummulites and some Alveolinae. 
Three boulders of Nummulitie limestones were found in the 
Schultz-River, an eastern affluent of the Lorentz-River (N's 796, 
797, 798. 1909). They are all of them gray limestones, rich in 
splinters and rounded quartz-grains, in which many large and small 
Nummulites present themselves. In part the Nummulites possess 
reticulated septalbands. By the side of Nummulina, Miliola occurs 
and perhaps also Operculina. 
Finally at the place where the Koekoek River flows into the 
Reiger River a limestone with scarce quartzsplinters was found 
(Nr 388. 1907), which contains besides dubious Heterosteginae, 
numerous Nummulites (largest size 15 m.m.) with retiform septal- 
bands. 
Whereas the Lepidocyclina-limestones described at the outset, and 
probably also the Operculina-Heterostegina rocks, belong to the 
Neogene, the Alveolina-Lacazina-rocks and the Nummulitie limes 
are unquestionably to be referred to the Eogene. The absence of 
Assilinae and Orthophragminae and the frequent occurrence of 
Nummulites with retiform septalbands, point to the fact that we 
have to do with the younger parts of the Eogene. 
Some very young clayey, Foraminifera-bearing rocks, easily decom- 
posing in water, were found south of the mountain-zone. In clay from 
Kruisheuvel near Sabang (Nr 107. 1907), which hill has partaken of 
the latest mountainfolding, numerous Rotalidae were found. Many 
Polystomellae occur in clay that occurs as a solid rock on Zuilen- 
heuvel, not far from Geitenkamp, (Nr 1774. 1907). A sort of clay, 
found near Alkmaar, is rich in several stratigraphically insignificant 
Textularidae and Miliolidae (Nr 258a. 1907). The three clays recorded 
here very much resemble the young tertiary marls, known from Timena 
in Northern New-Guinea. ') Probably also their ages are about the same. 
Finally we have still to record some non-typical Foraminifera- 
bearing rocks. A boulder from Alkmaar (N°. 224. 1907) is a glau- 
conitic, dark gray lime with Lithothamnium, Corals, ? Bryozoa, ? 
Orbitolites and a very small Nummulinida, probably Polystomella 
of undoubted Tertiary age. In the Bibis River a solid limestone was 
found, containing besides numerous Lamellibranchiatae and Corals 
also small individuals of Polystomella ef. eraticulata F. and M. This 
rock is also Tertiary. 
') L. Rorren. Nova Guinea, |.c., p. 34. 
