Hitman Physiology. 125 



second, %ing 15 feet. If a horse had the speed of the fly, in 

 proportion to size, it would move across the earth like lightning. 

 One kind of fly has wide, branching eyes, like the hammer- 

 headed shark, but far wider in proportion. The proboscis, 

 with its lancets and suckers, is a most wonderful instrument, 

 while the ovipositer egg-placer of the gadfly is made of four 

 horny tubes, one shutting within the other like a telescope, the 

 last ending in five points, of which three are long and hooked, 

 by which the extended tube pierces the skin of animals and 

 then holds fast until the eggs have been deposited. And this 

 machine, and all these machines of myriads of insects with the 

 instincts, of which they are instruments, we are told were 

 casually developed by accidental variations, and continued 

 upon the principle of natural selection ! Upon this principle, 

 the fly has also an eye with 4000 facets, each a distinct and 

 perfect eye, while the butterfly has 17,000, and the modella 

 and dragon fly, 25,000! 



One of the most curious instances of mechanical contrivances 

 in insects is that of the bombardier beetle, by which it dis- 

 charges from its abdomen, for defensive purposes, globules of 

 an acrid, pungent fluid which explode like a shell when they 

 come in contact with the air, the fluid acting upon the enemy 

 like nitric acid. Some of these beetles can make a dozen 

 successive discharges of this wonderful artillery. Open the 

 receptacle and the matter effervesces and evaporates in an 

 instant. This acrid explosive is secreted like the poison which 

 bees and wasps send through their stings, and serpents through 

 hollow or grooved fangs provided for the purpose poisons 

 secreted from the blood, made of most innocent food, and 

 such as no chemist can produce. And we are expected to 

 believe that these contrivances come by accidental variations, 

 natural selection, and the survival of the fittest ! 



The Honey Bee, in its structure, and its instincts, which 

 correspond everywhere to structure, is a wonderful illustration 



