NOTICES OF NEW BOOKS. 37 



points upon which a few details would be interesting to the 

 uninformed reader. To begin with, we are not told what con- 

 stitutes the difference between a Kangaroo and a Wallaby, nor 

 what is the derivation and meaning of the latter name. Pre- 

 sumably, like the former, it is of native origin ; but if there are 

 any tangible characters by which a Wallaby may be always 

 distinguished from a Kangaroo, it might have been well to point 

 them out. A table of classification would have been a useful 

 addendum to the Introduction. Then we should like to know 

 what is the number of species of Macropodidce at present known 

 to exist, and how many of them have been made known and 

 described since the publication of that epoch-making work, 

 Gould's ' Mammals of Australia,' which was completed in 1863. 

 Their respective distribution in Australia and New Guinea is 

 another point upon which some information would be acceptable, 

 as well as on the question whether there is any species common 

 to the two countries. Probably not ; though there may be some 

 which are very closely allied. Again, looking to the physical 

 aspect of Australia, and to the existence of great central deserts — 

 which seem (in the case of man at all events) to create an almost 

 insuperable barrier to overland communication, say between East 

 and West, or between South and West — one would like to know 

 whether any of the Macropodidce find their way across Central 

 Australia, or what are the limits of distribution so far as has 

 been ascertained. 



In regard to the habits and mode of life of the Australian and 

 New Guinea mammals there is a woful lack of information ; and 

 it is little less than a reproach to those who write about them, 

 that they have not collected more facts from colonists who, 

 dwelling amongst or within measurable distance of these, to us, 

 unfamiliar creatures, could tell us, if they would, a great deal 

 more than we now know about them. We already hear of the 

 threatened extinction of certain species whose skins are exported 

 by the thousand to the London market ; and it would seem as 

 if some of them were to pass away, leaving us with little more 

 knowledge concerning them than we possess in regard to forms 

 already extinct. This surely ought not to be. The members of 

 such scientific societies as have been long formed in Australia and 

 Tasmania, and more particularly the staff of the Australian 

 Museum, Sydney, should find opportunities for supplying this 



