510 Willis.— Endemic Genera of 
and that they received these floras in accordance with the principles of Age 
and Area, the endemic genera in them being in general simply the younger 
genera that have not yet spread very far. 
A little more must be said to make clear the position with regard to 
relic endemics, and possibility of genuinely oceanic islands. Nothing that 
has been said above is to be read as denying that either of these may exist, 
but it is clear from the figures that they are unimportant as compared with 
the endemics which are not relics, and the islands which are not truly 
oceanic, but have been peopled with plants by land connexions. There is 
Diagram 6. 
an appreciable sprinkling of plants, such as Ginkgo for example, which are 
now confined to small areas, and which we know from geological evidence 
to have been formerly widespread ; but these are but few and far between in 
the grand total of endemics. In the mass, it is no longer possible to look 
upon endemic genera as being survivals ; evidence must be definitely brought 
up in each individual case in which it is desired to prove that an endemic is 
a survival. And the same general statement is true with regard to the 
oceanic nature of islands. It is not possible to regard islands, in the bulk, as 
having received their floras across the present existing wide stretches of 
water ; they must in general have received their floras by way of land con^ 
