230 



NATURAL HISTORY. 



the necessary wound in the skin of the animal whose 

 blood is to be sucked. 



394. The head of the insect is furnished with certain 

 appendages called antennae, supposed to be organs of 

 feeling, and perhaps of hearing also. They are various 

 in form, and commonly very beautiful, especially when 

 examined with the microscope. In Fig. 180 you have 



Fig. 180. Variously-formed Antennae of Insects. 



a variety of them represented. There are other feelers 

 called palpi, which are usually much smaller and shorter. 

 The antennae probably act as feelers in regard to objects 

 a little distance off, while the palpi do the same for sub- 

 stances close by the mouth of the animal. 



395. The senses of Insects are all acute ; and yet the 

 organ of smell has never been discovered, and in most 

 no organ of hearing can be found. The organs of vision 

 are generally plain to be seen, and are often exceedingly 

 prominent objects as we look at the insect. Very com- 

 monly the eye is a multitude of small eyes. In the com- 

 mon house Fly there are 4000 of them, and some insects 



Fig. 181. Head and Eyes of the Bee, showing the Division into Facets. 



