607 
distinguished, even when separate individuals are examined. A minute 
study of thin sections is, therefore, most often disappointing. It is 
even more difficult in the case of Nummulites: the specific differences 
of the Indian species being very little known, so that even the 
determination of isolated individuals is often difficult. 
Both for geological and for paleontological reasons we shall, 
therefore, confine ourselves to a brief description. 
1). The Lepidocyclina limestones. Boulders with Lepidocyclinae 
have been found in the Lorentz-River near Sabang and Geitenkamp, 
in the Bibis-River (Van der Sande-River) and where the Koekoek- 
River, flows into the Reiger-River’). Solid rock of Lepidocyclina 
limestone was detected in the Resi-chain, the Went-mountains, on 
Mount Permadi and near the Perameles-bivouac. The limestones 
belong to various types. 
Most numerous are pure gray to brownish-gray limestones, inva- 
riably distinguished by the occurrence of large Lepidocyclinae. In 
addition mostly Heterosteginae and often minute Nummulites occur. 
(Boulders: Sabang no. 85. 1907, 111a. 1907, Geitenkamp no. 195. 
1907, Bibisriver no. 544. 1909, Koekoekriver no. 385. 1907; Solid 
Roek: Went-mountains no. 631. 1909, and Perameles Bivouac nos. 
629 and 930. 1909). The diameter of the Lepidocyclinae is 
mostly over 15 mm., in one boulder (544. 1909) even more than 40. 
They are macrospherical and the first chamber is completely 
invested by the second. The fossils are slightly lenticular and do 
not possess a distinct median tubercle. Columns of an intermediate 
skeleton are sometimes absent; they occur, however, in most fossils 
and are distributed irregularly over the whole test. They are 
clearly coniform, their diameter is mostly smaller than that of the 
lateral chambers, sometimes they become bigger and invest the 
lateral chambers in the tangential section. These Lepidocyclinae 
belong to the group of the Lepidocyclina insulaenatalis J. a. Ch. 
The Heterosteginae can hardly be distinguished from the recent 
H. depressa d’Orb.; in one fragment (544. 1909) the nummuliform 
portion is strongly developed, so that the fossils resemble H. 
margaritata SCHLUMBERGER’), 
The Nummulites belong to the minor forms intermediate between 
Nummulites and Operculina, of which i. a. Versurk has described 
N. Niasi I] and N. Dungbrubusi. Their diameter is only 2 m.m., 
the number of whorls is 3 to 4. They resemble Nummulites in 
') For topographical details see the sketch-map in Bulletin 64 of the “Maat- 
schappij ter Bevordering van het Natuurkundig Onderzoek der Ned, Koloniën’, 1910, 
3) C. SCHLUMBERGER. Samml. Geol. Reichsmus. Leiden (1). VI. 1902, p. 250—252, 
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