314 



Habits of the Greenhouse White Fhj 



Instar III (Fig. 22). 



General appearance and habits as in the preceding stage, but 

 larger, with the wax fringe narrower and the marginal spines shorter. 

 It is 0*52 mm. in length, with six abdominal segments, and the 

 metathorax differentiated. Mouth-parts of the same general structure 

 as in the first and second instars. 



Fig. 23. Les;. 



Fig. 22. Third instar. 





Fig. 24. Antenna. 



DP 



Fig. 25. Vasiform orifice. 



Tracheal system. As in the previous stage. 



Legs (Fig. 23). The legs are very small, functionless for locomotion, 

 and the structure as in the preceding stage. 



Antennae (Fig. 24). Each consists of two segments. The basal 

 one is broad and carries a spine distally ; the second is hairy and 

 characteristically hooked. 



Vasiform orifice (Fig. 25). 



