CREATION BY LAW. 271 



vast range of correlations between the different 

 kinds of feather and the different Families or 

 Species, and between different parts of the body 

 in the same Species. But there are two Cor- 

 relations of Growth in respect to feathers which 

 are constant. In all cases, (excepting, of course, 

 the Wingless Birds,) the feathers which grow from 

 the fore-arm and finger-bones, constituting the 

 Wings, are comparatively long, strong, tapering, 

 elastic, and with thin lateral filaments, which 

 filaments are closely hooked together by means 

 of minute teeth fitting into each other, so that the 

 whole shall form one continuous surface or web. 

 This is a Correlation of Growth between one par- 

 ticular kind of feather, and one particular member 

 of the body, which, in all Birds capable of flight, is 

 constant, and amounts to a universal Law. Now 

 let us contrast this with another Correlation of 

 Growth which is equally constant. On the side of 

 the head of all Birds, there is a patch of feathers 

 of peculiar structure, with fine and slender shafts, 

 and with the lateral filaments not hooked together 

 as in the other case, but, on the contrary, always 

 separated from each other — the whole series form- 



