1370 THE STORY OF THE UNIVERSE 



feather of gills they are exactly like those which 

 we saw just now in the white Cucumaria. Yes ; here 

 is another instance of the same custom of repetition. 

 The Cucumaria is a low radiate animal the sea- 

 slug a far higher mollusk; and every organ within 

 him is formed on a different type; as, indeed, are 

 those seemingly identical gills, if you come to ex- 

 amine them under the microscope, having to oxy- 

 genate fluids of a very different and complicated 

 kind ; and, moreover, the Cucumaria's gills were put 

 round his mouth, the Doris's feathers round the other 

 extremity; that gray Eolis's again, are simple clubs, 

 scattered over his whole back, and in each of his 

 nudibranch congeners these same gills take some 

 new and fantastic form; in Melibaea those clubs are 

 covered with warts; in Scyllaea, with tufted bou- 

 quets; in the beautiful Antiopa they are transparent 

 bags; and in many other English species they take 

 every conceivable form of leaf, tree, flower, and 

 branch, bedecked with every color of the rainbow, 

 as you may see them depicted in Messrs. Alder and 

 Hancock's unrivaled Monograph on the Nudi- 

 branch Molluscs. 



One sight more, and we have done. I had some- 

 thing to say, had time permitted, on the ludicrous 

 element which appears here and there in nature. 

 There are animals, like monkeys and crabs, which 

 seem made to be laughed at; by those at least who 

 possess that most indefinable of faculties, the sense 

 of the ridiculous. But, in the meanwhile, there are 

 animals in which results so strange, fantastic, even 

 seemingly horrible, are produced, that fallen man 



