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 wifh 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 mellifica ; 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 lateracl). Note that 

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



