5. GEOGRAPHICAL DISTRIBUTION. 
In the intermediate seas between the Euro-asiatic and the Australian con- 
tinents there is stretched out the largest and most numerously membered archi- 
pelago of the earth, with a fauna and flora derived partly from the West and 
partly from the East. Where do we now And the frontier of these two faunas 
and floras, which contrast so strongly with one another in their extreme forms; 
or do they pass into one another so insensibly that a sharply deflned frontier 
cannot be traced? It would be very premature to attempt a sketch of the 
geological history of this region of the earth in view of the quite insufficient 
knowledge available concerning the living and, especially, concerning the extinct 
fauna and flora of the Archipelago, for we are acquainted with only a small 
fragment of the latter (the extinct); we must content ourselves with an attempt to 
answer the above interesting question with the aid of the rather better established 
data of the present time’), and, in accordance with the character of our book, 
1) The status of geological knowledge as to Celebes is veiy defective as yet, though some valuable work 
has been done recently and more is to be expected from Drs. P. & F. Sarasin. In this state of things we 
have found it preferable to abstain entirely from discnssing the past history of the island, but give some of 
its literature, where references to further geological, palaeontological and mineralogioal papers are to be found: 
1S83. K. Martin: Wiss. Aufg., welche der geologischen Erforschung des Indisehen Archipels gestellt sind. 
(Lecture. Leyden, Brill). Id.: Die wichtigsten Daten unserer geologischen Kenntniss vom Niederl. Ost-iud. 
Arch. : Bijdr. taal- land- en volkenk. van Ned. Ind., uitg. ter gelegenheid van het B. intern. Congres der 
OrientaHsten te Leiden. Land- en volkenkunde. 1883, 17 'Celebes p. 23) with summary of literature. 
1S88. C. M. Kan: Bodengesteldheid der eilanden en diepte der Zeeen van den ind. Arch.: Tdschr. Ned. aardr. 
Gen. (2) V fVersl.), 202, Kaart IV. 
1890. K. Martin: Die Kei Inseln und ihr Verhaltniss zur australisch-asiatischen Grenzhnie, zugleich ein Bei- 
trag zur Geologic von Timor und Celebes: Tdschr. Ned. aardr. Gen. (2) VII, 241. Id.; Zur Geologic von 
Celebes: 1. c. 1891 VIII, 180. 
1890. A. Wichmann: Bericht iiber einc . . . Keise etc. II. Celebes. 1. o. (2) VII, 921 Tab. II; 1892 IX, 238. 
Id.: Die Binnenseen von Celebes: Petermann’s Mitth. 1893, 215 Taf. 16. Id.: Petrogr. Studien iiber den 
Ind. Arch. 1. Leucitgesteine von der Insel Celebes: Nat. Tschr. Ned. Ind. LIII, 315, with plate. 1895 
n. Zur Geol. der Insel Saleyer: 1. c. LW, 236 pi. V. 
1894. W. P. van Vliet jr.: De verticale ligging en de geologisohe bouw van Celebes: Tdschr. gesoh., land en 
volkenk. 9. Jaarg., 257 (with summary of literatui’e). 
1895. 1. W. Retgens: . . . Gesteenten van Celebes: .'Jaarb. Mijnwezen in Ned. Oost-Ind. 24 Jaarg., 124. 
1896. Encyolopaedie van Ned. Indie (by van dor Lith and others) I, 317 (s. a.). A general report on the 
geological formation of Celebes. 
1896. K. Martin: Zur Frage nach der Entstehung des ost- und westindischen Archipels: Geogr. Zeitschr. II, 376. 
It is nearly the same with the flora of the Archipelago. Though relatively much is already known, we 
are very far from a thorough knowledge, which would enable us to draw trustworthy conclusions. We, there- 
fore, likewise abstain from touching these questions, which are discussed in the works of Griscbach (Vege- 
tation der Erde 1872, Ges. Abh. u. kl. Schr. zur Pflanzengeograpliie 1880), Engler (Versuch einer Entwick- 
lungsgesohichte der Pflanzenwelt, insbesondere der Florengebiete seit der Tertiarperiode 1882), Drude (Die 
