216 From Matter to Man. 



average is but a blundering apprentice, and only 

 rarely becomes a journeyman. Thus the leg passes 

 through thousands of transformations, very few of 

 which could be pronounced perfect, although they all 

 answer their purpose more or less well. Starting 

 from the simple pseudopodia of the amoeba, and 

 passing on to the sting ray of the actinophrys, the 

 flagellum of the flagellata, the cilia of the ciliata, the 

 stiff striated flagellum of the noctiluca, the muscular 

 ambulatory setae of the higher ciliata, and the suctorial 

 tentacles of the acinetaria, we leave the protozoa and 

 follow the same limb through the bristles on earth- 

 worms and the myriad kinds of locomotors on centi- 

 pedes, spiders, crabs, lobsters, frogs, lizards, birds, 

 seals, bats, horses, dogs, and monkeys, until we come 

 to what we consider the well-proportioned leg of man 

 himself; and yet who can say it is the most useful 

 that could be constructed. In fact, we practically say 

 it is not, for we use stilts to give us increased height, 

 and bicycles to give us increased speed. 



After examining all nature's handiwork, we find 

 that she has no ideals, no set type, and no perfect 

 mould ; she is merely ever trying by practical experi- 

 ment and temporary model to .invent the mechanism 

 best fitted to the needs of each animal in its ever- 

 changing conditions of existence in water, air, or 

 on land ; but the result is not always a triumph, nor 

 even to her credit. Indeed, far from this being the 

 case, she even displays a want of judgment in not 

 adhering to a good type when found, for not only 



