p. W. xVwATI 



253 



property as some investigators think, but it is due to the refraction of 

 light ; this is clear since the colour seems to change as one sees it from 

 fresh points of view. 



Fig. 10. 



(iii) Heart-Sharped Organ (Figs. 12, 13, 14). {a) External appearance. 

 Every larva has this characteristic organ, which is cordate in shape 

 (Fig. 12) and is bordered with several rows of big pores, besides 

 which there are also minute pores in many tiers inside the boundary. 



In the centre of this organ there is a peculiar-shaped structure which 

 is due to the invagination of chitin. Just above the notch of this 

 organ is an aperture presumably functioning as the anus or the opening 

 of the waxy glands. On either side of this opening there are two 



