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greatest economical importance to man. But of animal 

 forms the Arthropods are the most important, and it is even 

 not improbable that, notwithstanding the comparative small 

 size of the individual, the- portion of the animal matter of 

 the world invested in them is greater than that devoted to 

 the Vertebrata : I say this with some hesitation, because it 

 is exceedingly difficult for the imagination to form any 

 adequate conception of the total amount of life in the waters 

 of the globe ; but, leaving this out of consideration, it is 

 highly probable that insects would actually outweigh the 

 terrestrial Vertebrata ; their ubiquity, and the enormous 

 numbers of their individuals and species, quite making up 

 for the small size of the individual. Whether this may be 

 the case or not it is at least certain that they are of enormous 

 material importance to the human race, and this is so well 

 known that I feel at liberty to do no more than mention the 

 economic value of Entomology, and of collections in so far 

 as they illustrate it. 



Before quitting the first part of my subject I will ask you 

 to recall to your minds the fact that the organisation of an 

 insect is a very complex and perfect affair, and must have 

 taken vast periods of time for its evolution, if it has been 

 evoluted. It is equally complex and perfect, — I think even 

 more perfect, take it as a whole, than that of the Vertebrata, 

 — and Palaeontology shows us that it is of equal or greater 

 antiquity. These facts, then, viz., the multitude of species, 

 their advanced structure, their presence in large numbers in 

 all parts of the world, their great antiquity, give them a 

 predominant importance as objects on which to base con- 

 siderations with regard to the distribution, variation, and 

 origin of species, and from this point of view their small 

 size becomes an advantage ; we can get together without 

 difficulty ten thousand specimens of a beetle or a butterfly 

 for comparison, but how could ten thousand elephants or 

 lions or tigers be brought together ? The extreme variety in 

 the modes of life, of vital activities and capacities, and of 

 ontogeny in insects, render them of great value for statistical 

 purposes, because the chances of error due to the existence 

 of some unknown biological point are thus much diminished. 



