VI 



ANTENNA TAMO UTH PARTH 



r.i 



The mechanism for sucking and stinging, which is occasionally very complicated, 

 and to which certain adaptations in the oesophagus (pumps, " fish trap " apparatus, 

 etc.), belong, cannot be here more exactly described. 



The mouth parts of the other Hexapoda must be referred to one or other of the 

 types depicted. 



The mouth parts of the Coleoptera are for biting and masticating, similar to those 

 of the Orthoptera ; the masticatory ridges of the anterior maxilla? are rarely trans- 

 formed into a sucking tube. 



The mouth parts of the Dermaptcra, Ephemeridcc, Odonata, Plecoptera Corrodent in. 



FIG. 311. Mouth parts of the Hemiptera. A, of Pentatoma. L, of Pyrrhocoris. 



as before. 



Lettering 



Ncuroptera, and Panorpata are also adapted for biting, and belong with various 

 deviations to the type of those of the Orthoptera and Coleoptera. 



The mouth parts of the Thysanoptera (Physopoda) hold a position intermediate 

 between the biting mouth parts of the Orthoptera and the sucking mouth parts of 

 the lihynchota. The mandibles are changed into piercing setre, and come to lie 

 within a short tubular proboscis, which arises by the growing together of the upper 

 lip with the anterior maxillse and the lower lip (posterior maxilla 2 ). The 2 pairs 

 of maxillfe have distinct palps and otherwise generally show the typical parts 

 variously modified. In the Triclioptcra the mandibles are rudimentary, the 2 

 pairs of maxilUe together form a sort of proboscis (for piercing and sucking), the 4 

 palps remaining separate on it. The palps, however, as well as the proboscis itself, 

 may disappear. 



In the A2)haniptcra (Fleas) the mouth parts are for piercing and sucking. The 

 mandibles are toothed ridges which, together with the upper lip form the sucking 



