TESTACEA. 15 



CHAPTER II. 



THE TESTACEA. 



As if Nature beheld some of her children with greater favour than 

 others, she has provided special means for their protection against wilful 

 or accidental injury. So delicate is the organization of many, that it 

 seems scarcely even safe from the pernicious influence of external impres- 

 sions. Hence the means of protection may correspond with their liability 

 to danger, rendering the slightest safeguard sufficient. 



Some of the larger animals may inflict most deadly wounds, by 

 teeth, by hoofs or horns ; and the smallest may diffuse a deadly and 

 irresistible poison, fatal to the greater part of the living beings around 

 them. 



Animals are provided with means and instruments, offensive and 

 defensive. But ttie greater part are on such an equality in this respect, 

 as to be neither superior nor inferior to others. Many are totally, and 

 many but partially, protected ; and it may seem singular that the most 

 precious and important organs are unsheltered. 



Thus no rational theory can be formed why Nature should have 

 been so evidently solicitous for the preservation of one class of beings, 

 while leaving others continually exposed to danger ; yet to say it can 

 have no object, would be alike presumptuous and absurd. 



The shelter provided by nature is chiefly bestowed on the lower tribes. 

 Though some are invested by shells, and others covered by spines or 

 prickles, it is rarely that anything more is done than merely strengthen- 



