VIII 



The complicated structure of the parts of the mouth of many 

 Cyprinoidea has found ample discussion, illustrated by figures, 

 in the text. 



In describing the Apodes their dentition is of great impor- 

 tance. To facilitate its description we have added in many 

 cases a figure of the dentition as it is seen on an impression 

 of the teeth in a bit of plasticine. For this purpose we introduce 

 a thin piece of this material in the opened mouth of the fish, 

 close it and extricate afterwards the piece with some caution 

 from the reopened mouth. In this way often teeth are indi- 

 cated, which otherwise are difficult to detect. 



We follow the law of priority and use the oldest name which 

 can with certainty be made out by the description, belonging 

 to a certain species. Its author is cited as the author of the 

 species and his paper is quoted in the first place. 



Mention is further made of all synonyms; besides, we have 

 quoted those papers, which contain a description of the species. 

 If it is a widely spread one, only those papers are quoted, 

 which contain a description of or give some informations - 

 others than those regarding locality only about Indo- 

 Australian specimens of that species. 



According to the international rules of nomenclature we 

 have neglected the generic names, as e.g. those of Swainson, 

 which are not accompanied by a description. 



We have recorded under: "iiomina indigena" those native 

 names, which seemed to us to be trustworthy. We are of opinion 

 that no great value ought to be attached to them, as the 

 unavoidable series of difficulties is still enlarged by the fact, 

 that the authorities for those names have mostly been European 

 ichthyologists and no linguists. 



There remains for us the pleasing duty of expressing our 

 thanks to Mr. C. PELTENBURG, head of the firm E. J. BRILL Ltd 

 of Leiden for the interest he took in publishing also this volume 

 and to Mr. J. F. OBBES, the able artist to whom we are indebted 

 for the faithful figures, which illustrate this volume. 



MAX WEBER. 



L. F. DE BEAUFORT. 



Eerbeek, Holland, July 1916. 



