39 



the Wheat Midge affects the wheat, and when mature they leave the clover heads, drop to 

 the ground, and either work themselves a short distance under the ground or hide amongst 

 dead leaves or other rubbish on the surface, and there enter upon the pupal stage of their 

 existence. Figure 12 represents the larva highly magnified, the hair line at the side 

 showing the natural size ; at h the head is shown retracted, and more highly magnified. 



The Pupa, or Chrysalis. 



Each larva having fixed on a suitable location, spins for itself an oval, compressed, 

 rather tough cocoon of fine silk, with particles of earth or other material adhering to the 

 outside, which makes it extremely difficult to discover them. Within this enclosure the 

 lar^a changes to a chi-ysalis, which is of a pale orange colour with brown eyes ; on the 

 froi-t of the head are two short conical tubercles, and behind these two long bristles. The 

 sheaths in which the antennae are concealed are curved outward, much like the handles of 

 an um. The duration of the pupa state of the early brood is about ten days. When 

 the fljT is about to emerge, the chrysalis works its way out of the cocoon to the surface, 

 and tken opening the fly escapes. 



The Fly. * 



Tie perfect insect is a minute two-winged fly, about the size and general appearance 

 of the common Wheat Midge. The head is black ; the antennse long, yellowish-red, with 

 sixteen or seventeen joints in the female and fifteen in the male. Wings nearly trans- 

 parent, «lothed with many short curved blackish hairs, which give them a dusky appearance; 

 each wiig has three longitudinal veins, the third either forming a fork, or else becoming 

 more or less obsolete towards the tip. Hairy fringe of wings, paler and composed of 

 longer hiirs than those on surface of wing. Abdomen fuscous, with black hairs above on 

 each segment; thorax black, and clothed with rather long hairs. The male has an 

 exteided pair of clasping organs on the hinder extremity; the female a long pointed 

 oviptsitor, about twice the length of the abdomen. 



Figure 13 represents the female fly with her four-pointed ovipositor extended ; at c 

 we hive a more highly magnified view of the tip of the ovipositor, clothed at its extremity 

 with short hairs. At h we have the head highly magnified, to show the structure of the 

 eye, he four jointed palpi and the basal joints of the antennae ; at c? we have a portion of 

 one -f the antennae much enlarged. The small lines at the right give the natural size of 

 the nidge. 



Figure 14 shows the male fly similarly enlarged, with highly magnified representa- 

 tions of the head at 6, the peculiar clasping organs at c ; the pedunculated joints of the 

 ante.n8e at c, which are more rounded and hairy than those of the female. At e the claws 



