THE ARREST OF THE BODY 141 



urchins, almost the same as those which tenant 

 the coast-lines of our present seas, crawled along 

 what arc now among the most ancient fossiliferous 

 rocks. Both of the forms just named, the Brachio- 

 pods and the Echinoderms, have come down to us 

 almost unchanged through the nameless gap of 

 time which separates the Silurian and Old Red 

 Sandstone periods from the present era. 



This constancy of structure reveals a conser- 

 vatism in Nature, as unexpected as it is wide- 

 spread. Does it mean that the architecture of 

 living things has a limit beyond which development 

 cannot go ? Does it mean that the morphological 

 possibilities along certain lines of bodily structure 

 have exhausted themselves, that the course of con- 

 ceivable development in these instances has actually 

 run out? In Gothic Architecture, or in Norman, 

 there are terminal points which, once reached, can 

 be but little improved upon. Without limiting 

 working efficiency, they can go no further. These 

 styles in the very nature of things seem to have 

 limits. Mr. Ruskin has indeed assured us that 

 there are only three possible forms of good archi- 

 tecture in the world ; Greek, the architecture of the 

 Lintel ; Romanesque, the architecture of the Rounded 

 Arch ; Gothic, the architecture of the Gable. " All 

 the architects in the world will never diJ'cover any 



