108 ILLINOIS BIOLOGICAL MONOGRAPHS [278 



EXPLANATION OF PLATE 

 Epipharynx and Hypopharynx and Assooated Parts 



Fig. 529. Psychoda alhipennis, lateral aspect. 



Fig. 530. Psychoda albipennis, caudal aspect. 



Fig. 531. Chironomus ferrugineovitiatus, lateral aspect. 



Fig. 532. Chironomus ferrugineovittatus, caudal aspect 



Fig. 533. Psilocephala haemorrhoidaUs, lateral aspect. 



Fig. 534. Psilocephala haemorrhoidaUs, caudal aspect. 



Fig. 535. Mydas clavatus, lateral aspect. 



Fig- 536. Mydas claz'atus, caudal aspect. 



Fig. 537. Scenopinus fenestralis, caudal aspect 



Fig. 538. Scenopinus fenestralis, lateral aspect 



Fig. 539. Lonchoptera lutea, lateral aspect. 



Fig. 540. Aphiochaeta agarici, caudal aspect. 



Fig. 541. Lonchoptera lutea, caudal aspect 



Fig. 542. Platypesa velutina, caudal aspect. 



Fig. 542a. Platypeza z-elutina, lateral aspect. 



Fig. 543. Eulonchus tristis, lateral aspect 



Fig. 544. Aphiochaeta agarici, lateral aspect. 



Fig. 545. Stratiomyia apicula, lateral aspect. 



Fig. 346. Stratiomyia apicula, caudal aspect 



Fig. 547. Empis clausa, lateral aspect. 



Fig. 548. Empis clausa, caudal aspect 



Fig. 549. Exoprosopa fasciata, lateral aspect. 



Fig. 550. Exoprosopa fasciata, caudal aspect. 



