216 Messrs. R. B. Newton and R. Holland on some 



Nummulites ; but it was reserved for P. van Dijk * in 1858 

 to first determine the forms and to identify tliem as ot 

 " Suessonien " age, the species being as follows : — Nummu- 

 lina depressa, Orb., N. hnticularis, Bronn, N. mamilla, 

 Honinghaus, and N. polygyrata, Deshayes. 



A further reference to these Nummulites was made by 

 C. de Groot f in a letter to Sir Roderick Murchison during 

 1863, a list of species being given which corresponded 

 exactly with van Dijk's of 1858. 



To Dr. R. D. M.Verbeek \ we are, however, indebted for 

 the earliest published figures and descriptions of Bornean 

 Foraminifera, issued in 1871. His specimens were obtained, 

 also from the southern part of the island, at Riam Kiwa, 

 Pengaron, &c, and were determined as Nummulites pengaron- 

 ensis (sp. n.), N. sub-Brongniarti (sp. n.), N. biaritzensis, 

 Archiac, and N. striata, Orb., var. / (var. now), Orbitoides 

 discus, Riitimeyer, 0. Pratti, Michelin, 0. papyracea, Or- 

 bigny, 0. Fortisi, Archiac, &c, all of which were referred to 

 the Eocene period. 



In 1878 Dr. K. von Fritsch § made a further study of a 

 similar series of forms from Southern Borneo, and described 

 them as occurring in the Orbitoidenschichten division of the 

 Eocene beds, under the following names : — Nummulites sub- 

 Brongniarti, Yerbeek, Orbitoides papyracea, Boubde, 0. ephip- 

 pium?, Schloth., 0. omphalus, sp. n.? } and 0. decipiens, 

 sp. n. ? 



In 1882 Prof. K. Martin || identified Orbitoides dispansa 

 and NummuJina in the Teweh district and near Martapura 

 (S. Borneo) as of probably Eocene age ; but such forms as 

 Cycloclypeus, Eotalia, Globigerina, Orbitoides, Textularia, 

 and Amphistegina, which came from Tungang, on the River 

 Barito, of South Borneo, he regarded as Miocene. Dr. T. 

 Posewitz ^[ next referred to the Foraminifera found near 



* " Over der Waarde van eenige Nederlansch-Indische Kolensoorten," 

 Nat. Tijdsch. NederL-Indie, 1858, vol. xv. pp. 139-158. 



t " Notes on the Mineralogy and Geology of Borneo and the adjacent 

 Islands," Quart. Jo urn. Geol. Soc. 1863, vol. xix. p. 515. 



J " I)ie Numtnuliten des Borneo-Kalksteines," Neues Jahrbuch, 1871, 

 pp. 1-14, pis. i.-iii. ; "De Numnmlieten uit den Eoceenen Kalksteen van 

 Borneo," Jaarb. Mijn. Ned. O.-Indie, 1874, vol. ii. pp. 133-161, plate 

 (=reprint of the 1871 paper). 



§ " Einige Eocane Foraminiferen von Borneo," Palfeontographica, 1878, 

 Suppl. vol. iii. pp. 139-143, pis. xviii., xix. 



|| " Neue Fundpunkte von Tertiar-Gesteinen ini Indischen Archipel ; 

 nach Sainmlungen von Horner, Korthals, Macklot, Miiller und Rein- 

 wardt," Samml. geol. Beicks-Museums Leiden, 1882, pp. 132-147. 



^[ "Geologische Notizen aus Central-Borneo (Das Tertiare Hiigelland 

 bei Teweh)," Nat. Tijdsch. NederL-Indie, 1884, vol. xliii. pp. 169-175. 



