XI 
Personally we had a large material at our disposal. The 
collection of the Museum at Amsterdam has been greatly 
increased of late years by material from the Indo-Australian 
Archipelago, partly collected by us. Part of it has already 
been described by us. 
Among the collections, which have not yet been described 
we mention the following: 
From JVias, made by Dr. J. P. KLEIWEG DE ZWAAN; 
from Borneo, made by Dr. H. A. LORENTZ, Dr. L. RUTTEN 
and Mr. W. J. TISSOT VAN PATOT; 
from Sumatra, made by Dr. L. P. DE Bussy, F. K. Baron 
VAN DEDEM, Dr. A. J. SALM, Mr. Vv. D. WERFF and Mr. E. 
C. A. HERBST, but above all by Mr. and Mrs. MOOLENBURGH, 
to whom we are indebted for a very rich collection; 
from Szmalur, made by Mr. E. JACOBSON, who made exten- 
sive collections in this island, the fishfauna of which was quite 
unknown; 
from Central and Southeast Celebes by Mr. E. C. ABENDANON; 
from the Fava Sea and the Lesser Sunda Islands collections 
of marine and freshwater fishes made by Mr. P. BUITENDIJK, 
the late Dr. G. A. J. vAN DER SANDE, by Dr. H. F. MINKEMA 
and Colonel G. F. TYDEMAN; 
from New Guinea and the Aru Islands made by Mr. N. G. 
B. HENDRIX; 
from Buton [sland made by Dr. P. TH. JUSTESEN. 
We are glad of this opportunity to thank the above-named 
collectors, but also Dr. J. C. KONINGSBERGER, and Dr. P. N. 
VAN KAMPEN, who enabled us to examine part of the material, 
collected during the cruises of the Research-steamer “Gier”. 
In other respects too we had the advantage of having the 
collaboration of Dr. J. C. KONINGSBERGER, director of “’s Lands 
Plantentuin” at Buitenzorg. 
We gladly repeat our thanks, which we had already the 
pleasure to express in the introduction to the first volume. 
We are glad to add our thanks to Major OUWENS, keeper 
of the Zoological Museum at Buitenzorg. 
Finally we must say a few words about the arrangement 
of our descriptions of the species and about the synonymy. 
With exception of a few species, which we had no oppor- 
tunity to study, our descriptions are based, if possible, on 
more than one specimen of a species. We had the opportunity 
