102 ILLINOIS BIOLOGICAL MONOGRAPHS [272 



EXPLANATION OF PLATE 

 Labium and other Parts 



Fig. 459. Heteroneura fiaviseta, caudal aspect 



Fig. 460. Heteroneura fiaviseta, mesal aspect 



Fig. 461. Loxocera pectoralis, caudal aspect. 



Fig. 462. Loxocera pectoralis, mesal aspect. 



Fig. 463. Tetanocera plumosa, caudal aspect. 



Fig. 464. Tetanocera plumosa, mesal aspect. 



W'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 leucozona, 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. Stomoxys calcitrans, 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 (Calliphoraj vomitoria, cross-section thru pseudotrachea 



(After Dimmock.) 



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



Dimmock.) 



Fig. 486. Oncodes 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. Siinulium venustum, 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 



