E. Hargreaves 



317 



Spines. In addition to the marginal and the eleven pairs of long 

 dorsal spines mentioned above, there are : a pair ventral to the vasiform 



Fig. 30. Leg. 



Fig. 29. Fourth instar, tracheal system. 



orifice; a dorsal pair at the anterior corners of the vasiform orifice; 

 a dorsal pair in the first abdominal segment; an anterior dorsal short 

 pair over the sides of the mouth-parts. 



Fig. 31. Antenna. 



A^i stj fe 



Fig. 32. Va.siform orifice. 



Dorsal pores. There are twelve pairs arranged as in the previous 

 stage. 



Vasiform orifice (Fig. 32). 



