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branous folds of the hypopharyngeal or ventral lining of the 

 mouth. There is a certain, short, broad, fleshy flap which 

 may be called the hypopharynx. From this basal sclerite 

 (fused submentum and mentum) arise the slender four-seg- 

 mented labial palpi, and the terminal lobes. The paraglossae 

 are distinct, thin, membranous structures with the basal por- 

 tion well chitinized and with a peculiar button-like chitinized 

 tip. The glossae are fused at their base, and show a well- 

 developed basal chitinous skeleton-plate. The membranous 

 portions of the glossae are also fused for about half their dis- 

 tance ; the apical halves, however, are free, and each one 

 bears a button-like, chitinized tip, like the tips of the para- 

 glossae. 



Make a drawing of the labium. 



Make a drawing of the cephalic aspect of the head showing 

 the fixed and movable parts. 



MOUTH-PARTS OF THE HONEY-BEE. 



Apis nielli fica ; order Hymenoptera. 



Most of the bees in alcohol (if an alcohol specimen is 

 used) will be found to have certain of the mouth-parts pro- 

 truding. 



These parts are the maxillae and labium, united at the base 

 and associated to form a sucking proboscis. Before the de- 

 tailed examination of these parts is begun the student should 

 discover the labrum and mandibles. 



Labrum. The labrum is small and oblong in shape with 

 its laterocephalic corners rounded. The breadth (lateral) is 

 about three times its length (caudo-cephalic). 



Mandibles. Partially concealed beneath the labrum are 

 the spoon-shaped mandibles. With forceps or needle, press 

 the mandibles apart at their tips (press laterad). Note that 

 the mandibles are not toothed, but are rather paddle or spoon- 



