JAWS OF INSECTS. 



125 



268 



269 



the filaments are represented in Fig. 268, 

 separated to a little distance 

 from each other, in order that 

 their respective origins may 

 be distinctly seen ; the one 

 set (q) being prolongations of 

 the mandibles (j), and the 

 other set (p) being, in like 

 manner, prolongations of the 

 maxillae (m). Between these 

 filaments, and near their com- 

 mencement, is seen a pointed 

 cartilaginous body (g), which 

 is the glossa, or tongue; and 

 the aperture seen at its root is 

 the passage into the cesopha- 

 gus. The sheath is merely 

 the elongated labium, of which 

 the base is seen at l, in Fig. 

 268 ; but is represented in its whole length in 

 Fig. 269, where the groove for containing the 

 filaments above described, is apparent. 



In the mouths of the Annelida we often meet 

 with hard bodies, which serve the purposes of 

 jaws and of teeth. The retractile proboscis of 

 the Aphrodite, or sea-mouse, is furnished with 

 four teeth of this description. The Leech has, 

 immediately within its lips, three semi-circular 

 teeth, with round and sharp cutting edges : they 

 are delineated in Fig. 261, (p. 103), in their rela- 



