ILLIXOIS BlOl.OGICAI. MOXOGR.IPHS 



VOLUME 3 



OncojM Simiiliiim Castrophilus Gasirophilus Gaslrophflw 



487 489 490 491 492 



I'KTF.RSOX Ill-.AD AXD MOUTH PARTS OF DIPTERA PI. \ Tl" XX 



