20 EVOLUTION. 



Rudimentary Organs, 



Strong evidence in favor of the descent of present 

 species from other forms is furnished by what are 

 called rudimentary orgajis — imperfectly developed 

 and useless members. Crabs have eyes at the ends 

 of stalks, but in the Mammoth Cave are crabs hav- 

 ing stalks without eyes. Disuse has caused the 

 eyes to disappear, probably growing smaller in each 

 generation, but the stalks remain as rudiments and 

 prove the former possession of eyes by the remote 

 ancestors of the existing crabs. The right-whale has 

 teeth before birth, which are gradually absorbed and 

 disappear. The unborn calf has front teeth in the 

 upper jaw beneath the gum, but the adults have none. 

 The natural inference is that the ancestors of whales 

 and calves had such teeth fully developed. Many 

 birds, such as the ostrich and penguin, have abortive 

 wings ; their conditions of life not requiring the 

 exercise of these organs, they have diminished in size. 

 Rudiments of limbs are found in the python — a large 

 snake. The tail is traced through the animal king- 

 dom through various changes, till in some of the 

 higher monkeys and in man it is only a rudiment. 

 There it remains as evidence of the descent of man 

 from tailed animals. Otherwise we must suppose 

 that when the Creator made man out of the dust he 

 decided to give him a useless tail-bone. Lord Mon- 

 boddo, a Scotch lawyer of the last century, de- 

 clared that men had worn off their tails by sitting on 



