122 Human Physiology. 



ments for depositing them, tubular and extensible like teles- 

 copes, and furnished with pincers, saws, or drills; glue to fix 

 the eggs, silk to cover them ; in a word, a complex and wonder- 

 fully varied and perfect organisation. The secretions of insects 

 are more numerous and varied than those of the higher orders 

 of animals, among which are wax, honey, saliva, jelly, silk^ 

 gluten, varnish, scents, poisons, acids, smoke. 



Man has 529 muscles; a caterpillar may have 4,061., each r 

 of course, supplied with nerves and blood-vessels. An insect 

 can leap 200 times its length, and drag fifteen times its weight 



The insect world is full of examples of the most wonderful 

 and beautiful mechanism, and of adaptation of means to ends. 

 I have seldom seen anything which astonished me more than 

 a case of leaf insects and walking-stick insects deposited at one 

 time in the Crystal Palace. They looked precisely like a 

 collection of dry brown stems of plants and bright green leaves, 

 shaped, veined, and coloured in perfect imitation. It required 

 a close examination to be convinced that they had once been 

 living insects. It is evident that they were so formed to pro- 

 tect them from enemies that would devour them. Was it by 

 accident or done on purpose? 



The sheep carefully selects a place to have her lamb some 

 weeks before it is born; but insects make still more careful 

 preparations for those they are never to see. They bore into 

 trees, or the earth, or bodies of animals, and deposit their eggs; 

 they put them in silken bags with a provision of food, and 

 hang them up on trees, fasten in leaves, cover them with silk 

 or varnish, always where the grub can find its proper food. 

 Some lay 50 eggs, the queen bee lays 50,000, some ants a 

 much greater number. 



The transformations of insects are infinitely curious. The 

 gnat, or mosquito, lays its eggs on water, joining them together 

 to form a boat which no storm can upset. The young 

 mosquito is an ugly and voracious swimmer, devouring animal- 



