K. Hargreaves :U:] 



are two pairs of thoracic spiracles arranged as in the preceding stage, 

 and two pairs of abdominal situated in the first segment and at the 

 sides of the vasiform orifice respectively. A pair of thick tracheae are 

 given off from the dorsal system with evidence of a pair of spiracles, 

 as in the first instar. 



Legs (Fig. 19). The legs are much smaller than in the first instar, 

 and they are functionless as ambulatory appendages. Each consists 

 of three segments the homology of which could not be determined with 

 certainty. But it seems probable that the trochanter and tarsus are 

 absent. No spines are present. 



Antennae (Fig. 20). The antennae are exceedingly small, and 

 each is made up of two segments, the basal one having a short 

 spine near the middle, and the distal one being covered with very 

 short hairs. 



Li^f 



Fig. 20. Antenna of second instar. Fig. 21. Vasiform orifice and ventral spines. 



Spines (Fig. 16). In addition to marginal spines there are — a long 

 dorsal pair over the anterior end of the mouth-parts; a short dorsal 

 pair on the first abdominal segment ; a long dorsal pair at the anterior 

 corners of the vasiform orifice ; a very short pair at the posterior sides 

 of the vasiform orifice; a short ventral pair beneath the vasiform 

 orifice. 



Vasiform Orifice (Fig. 21). 



Dorsal pores (Fig. 17). On the dorsal surface are six pairs of pores, 

 which I take to be the openings of the wax glands, the secretion of which 

 covers the general surface of the body. They have a peculiar and 

 characteristic appearance. My preparations were stained with acid 

 fuchsin, and the pores appeared as small dark red rings, surrounded by 

 an area which was of a paler pink colour than the surrounding chitin 

 of the general surface. They are situated as follows : a pair in front of 

 the anterior dorsal spines ; a pair each near the thoracic and first 

 abdominal spiracles ; a pair in the fourth abdominal segment ; a pair 

 at the sides of the vasiform orifice. 



