28 MAMMALS OF THE 



question by Professor Dr. E. Selenka in a paper entitled: 

 »die Rassen und der Zahnwechsel des Orang-Utan ^)." Prof. 

 Selenka had at his disposal 300 skulls of Orang-oetan , 

 all collected in the countries along the right bank of the 

 Kapoeas-river (im rechtsseitigem Stromgebiete des Kapuas) 

 and this enormous material induced him to distinguish not 

 species but races or local-varieties^ 6 in number: three, the 

 males presenting cheek callosities, 1. Pithecus satyrus lan- 

 dakkensis, microcephalic and macrognathic; 2. P. s. batang- 

 tuensis , microcephalic and macrognathic ; 3. P. s. daclap- 

 pensis , macrocephalic and macrognathic: three, the males 

 without cheek callosities , 4. P. s. genepaiensis , microcephalic 

 and macrognathic; 5. P. s. skalauensis ^ macrocephalic and 

 brachy gnathic, with a sub-race (vielleicht nur eine Art 

 Familientypus ; diese Unterrasse verdient vielleicht nur den 

 Namen einer zufalligen , kurzlebigen Nebenform) P. s. 

 rantaiensis , microcephalic and brachy gnathic ; 6. P. s. 

 tuakensis, microcephalic and macrognathic. Professor Se- 

 lenka points out that, although these six races are sharply 

 lined, there is a very great variety within the limits of 

 each form. All these races are separated from each other 

 by either a river or a mountain. If we now consider that 

 there are living Orang-oetans too in the Sarawak-district, 

 in the south-eastern parts of Borneo, in the eastern part, 

 viz. : in Kotei , near Samarinda (W. T. Hornaday , Two 

 years in the jungle, 1885, p. 399) and perhaps in the 

 north-eastern parts and that a large material from those 

 localities studied after Selenka's method without doubt will 

 furnish another lot of races or local-varieties , then I think 

 every one will be convinced of the fact that the variability 

 in this species may be called endless, and subscribe the 

 conclusion laid down in my paper (N. L. M. 1895, p. 18), 

 namely that in this point it is in the Orang-oetan like in 

 the human being, »no two are exactly alike." 



1) Sitzungsberichte der Kön Preuss. Akademie der Wissenschaften zu Berlin, 

 19 Marz 1896, p. 381 sqs. 



iN'otes frona thie Leyden IMuseum, Vol. XIX. 



