Introduction: Wallace’s line. 
S3 
Survey, vol. IV, 363 — 377), is one of the few earlier zoologists who do not recog- 
nise Wallace’s line. His Indian Region, being part of the Indo-African Realm, 
has for its eastern frontier a line drawn west of the Moluccas and Aru. He 
sa s p 358)' “I fail to see any good reason for assigning Celebes and all the 
smaller Sunda Islands to the Papuan Province, as Mr. Wallace an d^^ others 
have done, but abundant evidence that such is not their real affinity.” And 
364- “The Australian Realm will be here restricted so as so embrace none 
of the islands situated to the westward of the Moluccas.”') His Insular or Ma- 
layan Province forms part of the Indian Region; it includes all the Sunda 
Islands, the Philippines and Celebes. His Papuan Province (p. 367) takes in 
the Molucca and Aru Islands to the west, but he considers the Molucca Group 
(p 364) to be a transitional link between the Indo-African and the Australian 
Realm, faunistically more loosely allied to the latter than to the former. 
K. Semper, 1880, in his work: “Die naturlichen Existenzbedingungen der 
T’hiere” TI, 136), discussed the problem fully. Though he found that facts do 
not speak everywhere in favour of \Vallace’s line, he was nevertheless inclined 
to adopt it in a general way; he explained the differences of the faunas to the 
east and west not, however, by former land-connections, but by the sea-currents 
transporting the animals, a hypothesis which, as far as we are aware, has not 
been accepted elsew'here. . 
O. Krummel, in 1882, published (see: Ztschr. wrss. Geogr. HI, 1, iai. i) 
an important map; “Tiefenkarte des australasiatischen Mittelmeeres”, on which 
he drew the line, but remarked (p. 2) that the depths of the Macassar Straits 
are quite insufficiently known and (p. 3) that in the Straits of Immbok 
only one sounding very near the coast of Bali, which was broken off 
at 50 fathoms, serves as a basis for the assertion that a deep gap in 
the chain of islands exists here! He further mentioned (p. 5) that there 
are no soundings whatever known from the three large gulfs of Celebes. 
K. Martin, in a lecture on the “Wissenschaftlichen Aufgaben, welche der 
geologischen Erforschung des Indischen Archipels gestellt sind”, held in Leyden 
in the year 1883, considered the line entirely erroneous. In his opinion (p. 28) 
the continental frontier between Asia and Australia is approximately idenhcal 
with the chain of volcanoes in the Archipelago. The same author says in a 
paper: “Die wichtigsten Daten unserer geologischen Kenntniss vom nieder- 
landisch Ost-indischen Archipel” (see: Bijdr. taal-, land- en volkenkunde Ned. 
Ind. iiitg. ter gelegenheid van het 6. intern. Congress der Orientalisten te Leiden, 
Land- en Volkenkunde. 1883, 27): “As far as our knowledge of to-day goes, 
Wallace’s line is geologically unjustifiable. . . . Nothing hinders us from drawing 
. Previously Bull. Mus. Comp. Zool. Cambridge, 1870-71, H. p. 381) Mr. Allen had uttered the follow- 
• uThe Australian Kealm embracing Australia, New Zealand, New Guinea and their dependent 
ManrTcludin. those to the eastward [?] as far as Timor and Celebes, is zoolo^cdly as distinct .” This 
il not atTll cle^r to us, but as this prominent writer later (see above) was quite intelligible, it is not necessary 
to discuss his former intimation. 
