102 ILLINOIS BIOLOGICAL MONOGRAPHS [272 



EXPLANATION OF PLATE 

 Labium and other Parts 



Fig. 459. Heteroneura flaviseta, caudal aspect. 



Fig. 460. Heteroneura flaviseta, mesal aspect. 



Fig. 461. Loxocera pectoralis, caudal aspect. 



Fig. 462. Loxocera pectoralis, mesal aspect. 



Fig. 463. Tetanocera pluuiosa, caudal aspect. 



Fig. 464. Tetanocera plumosa, mesal aspect. 



Fig. 465. Musca domestica, dorsal aspect of glossae. 



Fig. 466. Musca domestica, caudal aspect. 



Fig. 467. Musca domestica, mesal aspect. 



Fig. 468. Archytas analis, caudal aspect. 



Fig. 469. Archytas analis, mesal aspect. 



Fig. 470. Scatophaga furcata, caudal aspect of mediproboscis. 



Fig. 471. Scatophaga furcata, ventral aspect of distiproboscis. 



Fig. 472. Scatophaga furcata, mesal aspect. 



Fig. 473. Thelaira leucosona, caudal aspect. 



Fig. 474. Thelaira leucosona, mesal aspect. 



Fig. 475. Hydrotaea dentipes, caudal aspect. 



Fig. 476. Hydrotaea dentipes, mesal aspect. 



Fig. 477. Sarcophaga haemorrhoidalis, caudal aspect. 



Fig. 478. Sarcophaga haemorrhoidalis, mesal aspect. 



Fig. 479. Stoinoxys cal citrons, distal end, lateral aspect. 



Fig. 480. Stomoxys calcitrans, distal end, mesal aspect. 



Fig. 481. Lispa nasoni, distal end, mesal aspect. 



Fig. 482. Bombylius major, cross-section thru pseudotrachea. (After 



Dimmock.) 



Fig. 483. Ochthera mantis, cross-section thru pseudotrachea. 



Fig. 484. Musca (Calliphora) vomitoria, cross-section thru pseudotrachea 



(After Dimmock.) 



Fig. 485. Musca (Calliphora) vomitoria. an enlarged pseudotrachea. (After 



Dimmock.) 



Fig. 486. Oncodcs costatus, entire mouth-parts, caudal aspect. 



Fig. 487. Oncodes costatus, entire mouth-parts, lateral aspect. 



Fig. 488. Olfersia ardeae, distal end, lateral aspect. 



Fig. 489. Siniuliuni venustuvi, cephalic aspect of the labrum. 



Fig. 490. Gastrophilus equi, entire mouth-parts, caudal aspect. 



Fig. 491. Gastrophilus equi, sagittal section thru mouth-parts. 



Fig. 492. Gastrophilus equi, entire mouth-parts, cephalic aspect. 



