154 
tenuis were already known to inhabit the Malay Archipelago; they have not been observed 
outside that region so far I know. #. terebratus Darwin was not known to occur in the 
Malay Archipelago: Darwin reported, that the habitat of this species was unknown to him. 
In two recent papers (one! of BorrapaiLe and one” of ANNANDALE) this species is mentioned, 
as probably occurring in the Maldive and Laccadive Archipelagoes and at Ceylon. This is, of 
course, by no means improbable; but as these specimens did not show the peculiar structure 
of the basis, which struck Darwin and caused him to give the species its name and 
which is indeed very striking, some doubt remains whether the above-named authors really 
met with it. 
There is, after all, to judge from our present knowledge, some reason to admit that 
the Malay Archipelago has its special fauna of species of La/anus. Of course this cannot be 
proved, since any species, which at present is known from that region only, may afterwards 
be found to occur outside it. And even the great number of species that have been observed 
in this region does not prove much in this respect. In this connection, I wish to point out also, 
before leaving the subject, that several species of Aalanus have been observed in regions 
bordering on the Malay Archipelago, which seem to be absent in that region itself: namely 
B. nigrescens Lamarck from West-Australia, 4. cymézformzs Darwin from Madras, B. carenatus 
Gruvel from Akyab (Burma), 4. a/Zum Darwin from Ceylon and Australia, 2. vestitus Darwin 
and &. zmperator Darwin from New South Wales, and &. aeneas Lanchester from Manaar. 
But here again the same must be kept in mind, namely that no matter how carefully a region 
may be explored, several species may still be found there which hitherto have escaped observation. 
In consequence of the difficulty of the determination, it is even possible that one or more of 
the species described as new in this report, may after all turn out to be identical with one of 
those described already. For example, my new &. arcuatus may be found to be the same as 
Darwin's &. allium, as is explained by me in this report, where the description of my new 
species is given. The latest publications I have seen in which species of Balanus also were 
described, and which treat of the Cirripedes of East-Asia, are Paut KrwtGer’s paper (I. c.) 
which forms a part of Dor.Letn’s contributions to the natural history of East India, and Pivspry’s 
paper on the Barnacles of Japan and Bering Sea. Both papers were published in the course 
of 1911. According to Krtcrer, Balanus is represented in East Asia by 13 species and in 
Dortetn’s collections by 8, two of which only, viz. B. tntinnabulum and B. amphitrite, were 
collected also during the expedition of H. M. S. ‘Siboga’’, in the Malay Archipelago — but, 
as is well-known, and is said already (p. 153), these are both species with a world-wide 
distribution. Of the other six species of Krier, one (2. coro/liformis) may remain undiscussed 
here, it being one of those which I propose to include in a new genus; one (2. tzgonus), which 
is represented by numerous samples collected in Japan waters, is, according to Darwin, found 
also in the Malay Archipelago, and in Australia; three (B. crenatus, B. rostratus and B. cariosus) 
which were collected also in Japan, are species known hitherto from only temperate and colder 
' BORRADAILE, 1. c. 
° ANNANDALE, N., On the Cirripedia (of the Gulf of Manaar). In HERDMAN’s Report on the Pearl Oyster Fisheries, published 
by the Royal Society, 1906. 
26 
