r 

 192 MODERN IDEAS OF EVOLUTION 



flower as the most delicate and elaborate pencilling 

 of colour. To attribute the marvellous beauty of an 

 Argus pheasant or of a bird of Paradise to the taste of 

 the hen bird can scarcely be characterised as any 

 thing short of a base superstition ; while it is abso 

 lutely irrational as a matter of science, since it is 

 attributing an effect to that which cannot be an 

 efficient cause. 



Most persons have seen the beautiful Etiplcctella 

 aspergillum, or * Venus flower-basket, now somewhat 

 common in museums and private collections, but few 

 perhaps have minutely examined its structure. A 

 little observation enables us to see its regular cylin 

 drical form and graceful cornucopia-like curves, com 

 bining strength with beauty ; its framework of 

 delicate silicious threads, some regularly placed in 

 vertical bundles, others crossing them, so as to form 

 rectangular meshes, and still others placed diagonally, 

 so as to convert the square meshes into a lace-like 

 pattern. Without this framework are accessory spi- 

 cules placed in spiral frills, and at the top is a singular 

 network of silicious fibres closing the aperture, while 

 there are long silky threads forming roots below. 

 This structure, so marvellous in the mechanical and 

 aesthetic principles embodied in it, is the skeleton of 

 a sponge ; a soft, slimy, almost structureless creature, 

 which we find it difficult to believe in as a veritable 

 animal ; yet it is the law of this creature, developed 

 from a little oval or sac-like germ, destitute of all 



