168 ENDEMISM AND DISTRIBUTION [pt. ii, ch. xv 



hindered by surrounding barriers. Instances are given of the 

 space occupied by endemics, beginning with very minute areas, 

 and going on to larger; the latter show no break as one goes on 

 to areas larger again, up to any size possible for a species. No 

 difference can be seen between endemic and non-endemics. 



It is shown that endemics are distributed in "wheels within 

 wheels" (cf. maps); and that other features obtain in their dis- 

 tribution, of which a brief list is given on p. 166. None of these, 

 or but few, can be explained on the supposition that endemics 

 are local adaptations, or are relics, and the only possible explana- 

 tion, for the vast majority, seem to be that provided by Age and 

 Area and Size and Space, that, in general, they are young 

 beginners, descended from the " wides." 



The most important general featiu-e in the distribution of 

 endemics is probably that it is always of the "hollow curve" 

 type (fig. on p. 162) with most species on the small areas, 

 and numbers rapidly decreasing upwards to the large. This same 

 type of distribution proves to be the rule for all genera, however 

 large they may be, and however large an area they may occupy. 

 Endemics simply present a miniature of the general distribution 

 in the world. 



