102 ILLINOIS BIOLOGICAL MONOGRAPHS [272 



EXPLANATION OF PLATE 

 Labium and other Parts 



Fig. 459. Heteroneura ftaviseta, caudal aspect. 



Fig. 460. Heteroneura flaviseta, 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. 



»^ 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 leucocona, mesal aspect. 



Fig. 475. Hydrotaca dcntipes, caudal aspect. 



Fig. 476. Hydrotaea dentipes, mesal aspect. 



Fig. 477. Sarcophaga haeniorrhoidalis, caudal aspect. 



Fig. 478. Sarcophaga haemorrhoidalis. mesal aspect. 



Fig. 479. Stonwxys calcitrans, distal end. lateral aspect. 



Fig. 480. Stonwxys calcitrans, distal end> mesal aspect. 



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



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



Dimmock.) 



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



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



(After Dimmock.) 



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



Dimmock.) 



Fig. 486. Oncodcs costattts, 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 venustuni, 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. 



