Wallace's Line and the Distribution of Mammals

Abstract

THE very definiteness of ‘Wallace's Line’, A which threads its way with precision, though without much apparent geographical reason, between Borneo and Celebes and between the almost contiguous islands of Bali and Lombok, and so marks the boundary between the Oriental and Australian zoogeographical regions, must have raised a doubt in the mind of many a zoologist; and sometimes the doubt seems to have been justified. In an introduction to the most important analysis which has been made in recent years of the facts of mammalian distribution bearing upon the authenticity of Wallace's boundary, Dr. W. K. Gregory cites two serious criticisms.