198 AN KSSAY ON THE DEVELOPMENT OF THE MOUTH PARTS OF CERTAIN INSECTS. 



riaie III. 



Fig. 1. Moulh structures of Asilklti; — Laj>hria sp. a, maxilla from front ; 6, same from liebiad ; c, labium ; d, lab- 

 rum ; e, transverse section of moutli at junction of galea and subgalea. 



Fig. 2. Moutli structures of Ramphomyia longicauda. a, tlie labium ; b, maxilla ; c, extension of front of head ; 

 d, relation of this extension to the labium. 



Fig. 3. Galea of an Andrena allied to vicina. 



Fig. 4. Mouth parts of Bittacus strigosus. a, mandibles and labrum ; b, maxilla and labium ; c, mandibles and 

 labrum — epipharynx of Panorpa rufescens. 



Fig. •'i. Labial structures of Erhtalia tenax. 5", transverse section at about middle ; 5^ same at about tip. 



Fig. 6. Labial structure of Bombus sp. 6", transection at about middle ; Ci, same made near tip. 



Fig. 7. Labium of Harpalus calignosus. 



Fig. 8. Maxilla of Periplaneta orientalis. 



Fig. 9. Maxilla of Perlid larva. 



Fig. 10. Epipharynx of Eriatalis tenax. 



Fig. 11. !Mouth parts of Bibiosp. a, maxilla from behind ; 6, same in front ; c, transection made near the base. 



Fig. 12. Labium of Bombus fervidus ; the transections are lined to the portions referred to. 



Fig. 13. Labium of Chrysops viitatus ; the transections are lined to the parts referred to. 



Fig. 14. Labium of iJcnneiid »iwc«ras. 



Fig. 15. Maxillse and labium of Bombus, showing the relation of the parts to each other. v 



Fig. 16. Maxilla of Sialis. 



Fig. 17. Maxilla of Eydrophihis from upper and lower surface, redrawn from Comstock. 



Fig. 18. Maxilla and labium of Ptcromalus, redrawn from Ashmead. 



Fig. 19. Maxilla of Pronuba, male. 



Fig. 20. Maxilla of Nemognatha. 



Fig. 31. Maxilla of Pronuba, female. 



Fig. 23. Mouth parts of Locusta from Kolbe. i, labrum ; ii, mandibles ; Hi, maxillas ; iv, labium. 



