XI 



Personally we had a large material at our disposal. The 

 collection x)f 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 Nias, 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. v. 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 Simalur, 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 Java Sea and the Lesser Sunda Islands collections 

 of marine and freshwater fishes made by Mr. P. BuiTENDljK, 

 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 Island 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 



