250 THE CANADIAN ENTOMOLOGIST. 



Second Nymphal In^tar. 



Form as in the first stage, perhaps a Httle less broad in proportion 

 to the length. Rostrum as before, except that it is perhaps a little less 

 stout. Antennae still blunt, short and stout, but not so club-shaped. 

 They now begin to show two equal joints. The legs as before, the 

 first pair not quite so broad proportionally, with the blunt apical 

 femoral tooth beginning to show as an undulation in the inrier side of 

 the femur. The tibi^ of the second and third pair are better provided 

 with spines, which increase in number distally. The termmal combs very 

 apparent. 



Size : Long., 13 mm,; lat. not measured, dimensions being taken 

 from moulted skins. 



Air-tube, 2.7 mm. 



The survivor came to the second moult in nine days, the other two 



in six. These died on the 21st, due to their being carried about in 



water. 



Third Nymphal Instar. 



Form, not greatly changed from the preceding instars, except for 

 slight variations in proportions. 



Rostrum, much as before, but a little slimmer. In this instar the 

 tactile hairs at the extremity of the proboscis are quite noticeable. 



AntenucC appear imperfectly three-jointed in this instar. The suture 

 separating the basal joint is quite noticeable, and that between the second 

 and third joints shows as an incision in the outer margin of the antennae, 

 from which a little impressed line goes about half way across. Below 

 and above this indentation are two prominences, the beginning of the 

 lobes of the segments. Both prominences are armed with a stout spine, 

 that of the third joint being about twice as thick as that of the second. 

 The third joint appears to be pitted at the rounded end. 



Thorax much narrower, distinctly trisegmenlate. Head closer to 

 the adult shape, the eyes flattened on the inner side, and quite prominent. 

 The wing-pads first appear in this instar, though very small and 

 rudimentary. 



Legs and tarsi as before, with the spines of the second and third pair 

 of tibiae stronger, and the tibial comb more developed. In this instar the 

 fringing hairs of the second and third pair appear, scattered on the femora 

 and sparse on the tibite, but quite long. 



The false stigmata are quite noticeable at the sides of the abdomen, 

 as darkened spots in the integument. The legs are now shorter than the 



