THE CANADIAN ENTOMOLOGIST 203 



September, and the adults linger on the trees until the cool weather 

 of early October. 



Both the nymphs and adults are very active. After hatch- 

 ing, the nymphs make their way to the leaves and can be found on 

 both surfaces, principally the lower. They appear to scatter con- 

 siderably after the early stages. In one instance only, early in 

 the season, a colony of nymphs was found, but during the re- 

 mainder of the season, all stages of the nymphs were found singly 

 on the leaves and scattered over the trees. When many nymphs 

 are present, their feeding produces a characteristic, whitish dis- 

 colouration of the upper leaf surface. 



The adults are extremely active and scatter soon after emer- 

 gence. On rainy days they exhibit a tendency to collect to a 

 certain extent on the foliage, and at these times many can be ob- 

 tained without difficulty. 



Egg. — Length 0.92 mm., width 0.15 mm. Translucent, 

 cylindrical, elongate, sides parallel; basal end rounded; neck bent 

 slightly to one side; slightly curved when viewed laterally. The 

 eggs appear to be laid singly in the last made growth of the twig. 

 The position of each egg is indicated by a blister-like elevation of 

 the bark about one-sixteenth of an inch in diameter. These 

 blisters may be either circular or oval. Each egg is firmly embedded 

 in the tissue under the bark with its long axis parallel to the twig 

 and with its cap facing the bark. Upon removing the blister- 

 like elevation of the bark, only a slight discolouration of the green 

 tissue indicates the presence of an egg. On account of their 

 translucence, they blend with the tissue and are easily overlooked 

 unless a careful search is made. The blisters are found anywhere 

 on the young twigs, sometimes in groups of two or three, but more 

 often widely removed from each other. 



First stage nymph. — Length L25 mm., width of head includ- 

 ing eyes 0.26 mm. Shape elongate, broadest at head and fore 

 part of abdomen, tapering posteriorly. Dorsal surface reddish 

 brown. Fine median white line on front of head and dorsal sur- 

 face of head and thorax. First and second abdominal segments 

 white. Dorsal surface of head, each thoracic and abdominal seg- 

 ment bearing transverse rows of hairs; several hairs on head and 

 a transverse row on posterior margin of each thoracic and abdo- 



