﻿VIU IN IRODLXTIOX. 



also iricludes the liitlc that is known of the geological history 

 of the M')notremes. and Hkewise takes cognisance of a remark- 

 able extinct group believed to have some affinity with the 

 latter. In a work of the present nature it would, however, 

 obviously be inadvisable to treat of the fossil forms in the 

 detail with which their recent allies are described, and, accord- 

 ingly, nothing more than a general sketch has been attempted. 

 In marked contrast to the fulness of our knowledge of the 

 Marsupials and ^lonotremes from the point of view of the 

 systematist, is our deficiency with regard to their habits and 

 mode of life, this being especially the case in respect to the 

 breeding-habits of the ^Monotremata. It is not to the credit 

 of the present generation that the working zoologist has for the 

 most part to rely for his knowledge of the habits of the greater 

 number of Marsupials upon observations — admirable enough 

 in their way— published many years ago, and the Author 

 cannot but hope that the appearance of the present little 

 volume may act as a stimulus to those having the opportu- 

 nities of increasing our knowledge on this subject, information 

 being most specially desirable with regard to the mode of life 

 of the smaller members of the group. 



R LYDEKKER. 



