290 THE ARTISTIC ANATOMY OF ANIMALS 



Finally, the progression of the body continuing, the limb 

 becomes oblique downwards and backwards ; it is now at 

 the termination of pressure (Fig. 121, c), and proceeds to lift 

 itself anew if another step is to be made. 



In conclusion, the inferior extremity of the limb describes, 

 from its elevation to its being placed on the ground, an arc 

 of a circle around its superior extremity (Fig. 121, D) ; 

 whilst, during the pressure, it is its superior extremity 

 which describes one around its inferior extremity, then fixed 

 on the ground (Fig. 121, D). 



If we simultaneously examine the two fore-limbs, we 



Fig. 121. — Swing of the Anterior Limb on the Point of 

 Pressure (after G. Colin). ^ ^^ 



A, Commencement of the pressure ; B, centre of the pressure ; C, termina- 

 tion of the pressure. 



remark that when one of them begins its pressure the 

 other ends it, and vice versa. 



As to the hind-limbs, the oscillations are similar to those 

 of the fore ones. In the second half of the pressure — that 

 is, when they are passing from the vertical direction (Fig. 122, 

 A) to extreme obliquity backwards (Fig. 122, C) — the effect 

 of their action is to give propulsion to the body. 



The fore and hind limbs make the same number of steps, 

 and the steps have the same length. 



The limbs of any quadruped— but we make special allusion 



