go The Insides and the Worf{ings of Living Things 



satisfied with the similarities which we find on the ground 

 that after all there is an ideal pattern for legs. If, however, 

 go further and compare the front leg of the crocodile 



we 



Fig. 22. Homologies Between the Front Limbs and the 



Hind Limbs of Vertebrates 



There Is a long section between the joint connecting the limb with the 

 shoulder or the hip girdle, and the next joint, which corresponds to the knee 

 or elbow. This is followed by a section in which there are two bones lying 

 side by side. Then there arc several small bones that make up the ankle 

 {A) or the wrist (W). Finally there are the bones that make up the hand 

 or foot proper, ending typically in five rows, constituting the skeleton of the 

 fingers or toes. Upper row, front limbs; lower row, hind limbs, a, man; b, 

 lion; c, wolf; d, duck; e, vulture; /, bat; g, crocodile; h, whale; /, seal; 

 k, halibut. From Gruenberg, Biology and Human Life, published by Ginn 

 & Company. 



with the wing of the eagle, the front leg of the horse with 

 the wing of the bat, or the front leg of the cat with the 

 flipper of the whale, we shall find remarkable similarities in 

 spite of the most diverse outward appearance, and in spite 



