480 THE MECHANICAL FUNCTIONS. 



cumstances must lead to great diversities in the 

 apparatus for mastication and for digestion, 

 in the organization of the senses, in the con- 

 struction of the instruments of locomotion and 

 of prehension, and in the general form of the 

 body to which these various parts are to be 

 adapted. Yet, amidst all these variations, we 

 may perceive the same laws of analogy connect- 

 ing the whole into one series, and assimilating all 

 these multiform structures to one common stand- 

 ard. The same organ, however modified in its 

 shape and size, however stinted in one, or deve- 

 loped in another, is ever found in its appropriate 

 place, and retains the same connexions with ad- 

 jacent organs, whether we seek it in the carnivo- 

 rous or the herbivorous quadruped, in the inha- 

 bitant of the land or of the water, in the denizen 

 of the frigid or of the torrid zone ; or in animals 

 of the most diminutive or most colossal statures. 

 As an example, we may take the vertebrae of 

 the neck. It is a universal law, that this part of 

 the spinal column shall, in every animal of the 

 class mammalia, consist of neither more nor less 

 than seven vertebrae. Whatever be the length 

 or shortness of the neck, whether it be com- 

 pressed into a small space, as in the elephant 

 and the mole, whether it be lengthened to allow 

 the head to reach the ground, as in the horse 

 and the ox, or whether it be excessively pro- 

 longed, to allow the animal to reach the tops of 



