18 COMPAEISONS OF STRUCTURE IN ANDIALS. 



It is not only in form and structure, in the 

 possession or absence of limbs, in the modifi- 

 cations of those limbs, in the possession or 

 absence of a brain and spinal cord, in the 

 possession or absence of the various organs of 

 the senses, and in the adaptation of those 

 organs for different conditions of being, that 

 the animal creation offers such an apparently 

 endless variation ; nor yet is it in size, though 

 the range of magnitude is from the Greenland 

 vsrhale to the animalcule, of which thousands 

 sport and play in a drop of water j but also 

 in the purposes, the final ends of existence, 

 for which animals were created, that this 

 boundless extent of variation obtains. In 

 multitudes of instances, indeed, purposes to be 

 answered by the existence of animals are 

 beyond our finite comprehension, yet reason 

 urges upon us the axiom that nothing is 

 created in vain; and it is not because our 

 imperfect minds cannot comprehend the whole 

 of the mighty scheme of creation, that we are 

 to doubt that er-en the minutest animalcule is 

 created for some specific object, and has its 

 appointed part in the great system. A doubt 

 of the final causes of the existence of all living 

 creatures, (plants included,) without exception, 



