MULTITUDE OF AIR-TUBES, 



405 



and the larger tubes only are shown, as it is im- 

 possible to represent the smaller ones so as to give 

 a clear view of their 

 arrangement ; they 

 would cover the draw- 

 ing like a cloud of the 

 finest and most deli- 

 cate lace -work. In 

 short, in insects, there 

 being no separate lungs 

 in a particular place, 

 as in the animal frame, 

 the air is necessarily 

 carried all over the 

 body, so as to be sup- 

 plied even to the most 

 minute parts ; thus the 

 lungs may be said to extend through the whole 

 body. 



As the reader has laid his finger on his pulse, or 

 felt his heart beating within him, or seen a drop 

 of blood ooze from his wounded hand, have the 

 questions never occurred to him, Have insects 

 blood-vessels, and a beating heart? And if so, 

 have they blood like ours ? Many a wise man of 



The Air-tubes magnified. 



