LECT. III.] THE SKULL IX MARSUPIALS. 69 



organs of the body. It has cost me but a moderate 

 amount of attention to this group (which I am now 

 taking up in earnest) to find in the skull ten good 

 diagnostic characters. These are easy to follow by 

 anyone at all familiar with the skulls of the higher 

 mammals. I must therefore beg the attention of the 

 human anatomist, who will at once see how curious 

 and suggestive these deviations are from what is nornial 

 in our own species, and indeed I may say also in most 

 of the higher kinds. Nevertheless, these deviations are 

 not confined to the Marsupials, but are to some extent 

 seen in many of the lower kinds of Eutheria, and are in 

 themselves nothing abnormal at all, but only so in 

 relation to, and comparison with, the standard we have 

 set up, by making our own structure the measure of all 

 others. Indeed, these peculiarities are so many stepping- 

 stones between us and our highest Mammalian relatives 

 and the forms that lie below ; we are not so isolated as 

 we have supposed ourselves to be. 



The things which strike the eye in the examination of 

 the Marsupial types of skull are as follows: 



1. In the basal region of the nose there are several 

 pairs of splint bones, belonging to the vomerine series, 

 besides the large middle vomer or ploughshare bone, 

 like that which sheaths the base of the partition of 

 the nose-labyrinth in us. 



2. That strong floor, tlie hard palate, which in us and 

 our congeners divides the cavities of the nose from 



