For Zoographers Only 309 



entitled ''Over mangaan Knollen in mesozoischen diepzeeaf- 

 •zettmgen van Borneo, Timor en Rotti, him beteekenis en 

 hun imjzer van Opstaan.''' ^ These papers show that on the 

 islands of Borneo, Timor, and Rotti, at an elevation of 

 about 4000 feet, very extensive deposits occur which a 

 microscopical examination shows to be composed of radio- 

 laria, together with the manganese nodules so characteristic 

 of the deep sea. In other words, Molengraff has found an 

 extensive area of deep sea floor raised to 4000 feet above 

 the present sea level. On the southeast coast of Africa, 

 W. M. Davis noticed the truncation by the present shore 

 line of extensive concentric terraces, traceable far inland, 

 which could only mean the down-faulting of a gigantic 

 block of material to bring the shore line into its present 

 state. It will be said at once that some of these changes of 

 level have taken place in zones known to be incomplete in 

 isostatic adjustment, but this is a matter of no moment 

 whatsoever in comparison with the fact that change of 

 level may be found to have occurred in the very areas 

 where the islands under discussion are found. Celebes does 

 not lie upon the continental shelf, and yet the island has 

 an obviously continental fauna, and the late Mr. WilHam 

 D. Matthew, my principal and very friendly adversary in 

 these arguments, has told me himself that Celebes has been 

 a source of no small worry to him. Cuba has similarly a 

 large fauna derived from the American continent, although 

 it does not lie upon the continental shelf. Vaughan, a 

 thoroughly conservative observer, beheves {in litteris) that 

 Cuba was quite possibly separated, by the down-faulting 



* Kon. Ak. Wet. Amsterdam 23: 1058-1073. (Reprint: 1-16.) 



