HISTORY AND CARE OF CHIMPANZEES 19 



materially. They were simultaneously engaged in studies of 

 insight of anthropoid apes, Koehler using chimpanzees at the 

 Canary Island Station, the writer observing an orang-utan 

 at the private laboratory of G. V. Hamilton in Cahfornia. 

 In the present investigation the writer has been able to profit 

 by the report of Koehler and he herewith gladly acknowledges 

 his obligations to that able and single-minded investigator. 



