CHAPTER II. 

 INSECTA. 



THE GRASSHOPPER. 

 THE PARTS OF THE BODY. 



(i) The foremost, or anterior, part is the head. (2) The 

 middle part is the thorax. (3) The hinder, or posterior, ringed 

 part is the abdomen. 



THE HEAD. 



1. Describe its shape and mode of attachment to the thorax. 



2. The two slender projections are the feelers, or antennae. 

 Observe how and where they are attached to the head. Use a 

 lens to count the parts, or segments, of which each antenna is 

 composed. 



3. Note the situation and shape of the eyes. Examine one of 

 the eyes under a microscope, using a one-inch objective ; make a 

 drawing of what you see. These eyes are compound, and each of 

 the parts is called a facet. 



4. Just in front of the compound eyes look for a pair of the 

 simple eyes, the ocelli. Find a third ocellus on the head, using 

 a lens if necessary. 



5. At the lower part of the front of the head is a movable flap, 

 the upper lip, or labrum ; raise it with the dissecting needle. Ob- 

 serve how it is hinged ; cut or break it off. 



6. This lays bare the true jaws, or mandibles. Examine their 

 black, toothed tips with a lens ; find, by prying, how they move. 

 Study their action in the live grasshopper, raising the labrum. Study 

 carefully the way in which they move, and how they are hinged ; 

 then remove with the forceps, and again examine thoroughly. 



7. Turn now to the back of the lower part of the head ; pry 

 back the lower lip, the labium ; carefully remove it. 



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