258 



ELEMENTARY STUDIES IN INSECT LIFE 



Mouth-parts. Taken collectively, all the organs which 

 aid in the mastication of food are called the month-parts. 



Labrum. The freely movable flap which is joined to 

 the ventral margin of the clypens is called the labrum, 

 or npper lip. (Fig. 19-1.) 



Mandibles.- By removing the labriim and clypens the 

 mandibles become visible. (Figs. 193, <-, 195, c.} Note 



FIG. 196. Inner view of 

 maxilla, ic, lacinia ; gl t 



FIG. 195. Front view of head, galea . p ^ palpus ; m , me m- 



with mandibles spread out. c, brane. Enlarged about five 



mandible ; <i, maxilla ; e, maxil- times, 



lary palpus ; /, labiuni ; gr, labial 

 palpus ; //, hypopharynx. En- 

 larged about uve times. 



the direction of motion in the act of chewing. Remove 

 one of the mandibles, and carefully draw it. 



Maxillae. (Fig. 195, rf.) After removing the mandi- 

 bles there appears another pair of jaws, the under jaws or 

 maxilla?. These are more complicated organs, and need 

 to be removed with some care. If the head has not been 

 removed from the body before this time, remove it now 

 and pin it with the back or caudal aspect uppermost to 

 a piece of soft wood or cork. Lift off the freely movable 

 flap, the labinm, of which we will speak later. (Fig. 



