' 4B4 



120°53' E. on the north- and 120°47' E. on the sonth-coast, an 

 orographical difference presents itself already between the northern 

 and the sonthern part. Here very accidented grounds, steep moun- 

 tains 2646 m. high, and deep valleys and ravines, yonder a more 

 hilly region in which only few mountains reach a height of 1000 m. 

 and more. This northern part is chiefly covered by a formation, to 

 which J. J. Pannekoek van Rheden has given the name of Reo 

 formation, and which consists of limestones — especially coral lime- 

 gtone — resting occasionally on eruptive rocks and sometimes 

 enclosing volcanic products. Here and there they are covered with 

 tuffas ^). Pannekoek writes regarding the organic remains that are 

 found: "A cursory investigation stated the presence of: Orbitoids, 

 "Corals, fragments of Spatangus, Natica, Corithium, Conns, Lima (Pla- 

 "giostoma), Ctenostreon, Gervillia, Isocardia, Teredina". A curious 

 mixture indeed. It is to be hoped that this "cursory" examination 

 may soon be followed by a more correct one. From the remark 

 that the strata of the isle of Rindja, "seem to be younger, most 

 "likely tertiary" we must deduce that he supposes the sediments 

 of the Reo formation to be of a mesozoic age, which however cannot 

 be the case. H. Zollinger has already drawn the attention to the 

 similarity of these strata with regard to their petrographic character 

 with those of the south-coast of Java (Besuki, Kediri) "). They have 

 entirely the character of neogenic rocks, as appears already from 

 the occurrence of Globigerina limestones ''). Pannekoek however 

 rightly makes distinction between these and the younger pleistocenic 

 coral limestones, as they are found in the isle of Longos in the 

 neighbourhood of Reo, On the bay of Reo they rest on andesite 

 conglomerate, ^j A continuation of the Reo formation is most likely 

 still found as far as the Kolitang Bay (Soho Kolitang) 'J20°77' E. 

 J. F. HoEDT found eastward from the extensive plain a low^ range 



i) Overzicht van de geographische en geologische gegevens verkregen bij de 

 Mijnbouwkundig-geoiogische verkenning van het eiland Flores. Jaarboek van het 

 Mijnwezen in Ned. Indië. 40. 1911. Batavia 1913. Verhandel, p. 217—218. 



2) Verslag van eene reis naar Bima en Sumbawa .... Verhandel. Batav. Gen. 

 V. K. en W. 27. Batavia 185Ü, p. 14. Remarkable is liis annotation accord- 

 ing to which at Badjo (meant is perhaps Padja) a day's journey behind Bari 

 a hot spring is found, forming a pond, on which a brownish mass floats, which 

 hardens in the air and can be used for tarring proas. 



^) J. W. Retgers describes likewise from Dangkawai 15 kilom. S. W. from 

 Reo, a limestone containing foraminifera. (.laarboek van bet Mijnw. 24. 1895. 

 Wet. ged., p. J35 ) 



•^j A. WiCHMANN. Bericht über eine .... Reise nach dcm Indischen Archipel. 

 Tijdschr. K. Nederl. Aardr. Gen. (2) 8. 1891. p. 194. 



