of the Mammary Organs of the Kangaroo. 459 



teat, its life has been destroyed in every instance which I have 

 hitherto met with. It seems therefore fair to infer in such 

 cases, that the organization and general condition of the mar- 

 supial young is intermediate between the state in which we find 

 other classes of mammalia whilst inclosed in the uterus and 

 after they have been brought forth; for it must be manifest, 

 that in such cases the re-union of the lips of the immature ani- 

 mal to the separated teat is prevented by an absence of those 

 powers of volition with which other newly born quadrupeds are 

 invariably endowed. Numerous other arguments, which I need 

 not now instance, might be brought forward in proof of the fact, 

 that the first period of extra-uterine existence in marsupial ani- 

 mals is intermediate between the two states which I have just 

 mentioned. 



Now, as somewhat more than a mere matter of curiosity, it 

 may be interesting to future inquirers to know at what period 

 the re-union of a separated marsupial young one from the teat 

 can be effected ; since at that period it may be presumed that 

 the immature animal is no longer receiving involuntarily the 

 nourishment of the mother ; and since we have reason to believe 

 that it is at this time that the intermediate state of existence to 

 which I have alluded will have ceased. 



This can only be known by repeated experimental examina- 

 tions, made by others whose opportunity must be much more 

 extensive than my own ; and for their information therefore I 

 have to state, that I have repeatedly separated from its adherent 

 teat the young of the kangaroo whilst perfectly naked and ap- 

 parently blind, and at a time when its size was not equal to that 

 of a large Norway rat ; and that I have in more than one in- 

 stance prevented a re-union for nearly two hours, with a view 

 of ascertaining how far a constant supply of milk under such 



circum- 



