20 ' THE CANADIAN ENTOMOLOGIST 



It is not known how long it takes for the eggs to hatch. First stage nymphs 

 were not found in the buds until July 20. At this time the buds were not ap- 

 preciably deformed. From this it appears that over two weeks are necessary. 

 After hatching the nymphs make their way to the small developing buds, crawling 

 between the folded parts and locating in a spot between the centre and the 

 outside of the bud. At first the young nymph is somewhat greenish, but later 

 assumes a yellowish tinge. On September 1 , or over a month later an examina- 

 tion of numerous well-defined galls showed nymphs in all stages of growth 

 except the first and the last stages. By the middle and last of September 

 many last stage nymphs were found. 



The cells containing the nymphs appeared to be unevenly and thinly lined 

 with a white cottony material. This material increased in bulk as the last 

 stage was approached, and cells containing nymphs of this stage usually had 

 quite a pad of material on that part of the cell directly over the back of the 

 nymph. The hairs on the dorsal part of the body also were covered with the 

 cottony down. 



The nymphs collected during the season were easily arrangeable into 5 

 stages based on their size, but the exact number of instars is not known, due to 

 the difficulty of keeping the same nymph under observation throughout the 

 season. Brief descriptions showing development of the nymphs, are given 

 below. The bodies of the nymphs of all stages are capable of considerable dis- 

 tension, and specimens showing the same dimensions of the head and wing 

 parts vary greatly in the sizes of their bodies, due no doubt to the amount of 

 food in them at a given time. 



In addition to the references to this species which are given in Van Duzee's 

 Catalogue, the following one may be noted — Felt., Key to American Insect 

 Galls, N. Y. State Mus. Bull. 200, 1917 (1918), p. 23, fig. 127. 



Egg. — Length 0.3 mm. Width 0.1 mm. 



Pearly white, smooth, elongate sub-pyriform, rounded at basal end and 

 tapering to acute point at opposite end which bears a fine hair about }/^ as long 

 as the fegg. Widest across basal third. A short, backward projecting stipe 

 arises from near the basal end. 



First nymphal stage. Length 0.3 mm. Width of head between eyes 0.1 mm. 



Colour lemon yellow; oval, broadest across thorax, abdomen tapering 

 slightly; body flat dorsally or slightly convex, segmentation indistinct. 

 Antenna whitish, short, projecting; eyes red; median dorsal light line running 

 through head and thoracic segments. Dorsal surface of head evenly and 

 lightly browned, posterior to this area are 2 transverse light brown bands on 

 the thorax and posterior to these bands are many fine transverse brown lines 

 on the abdomen. Lateral edges of abdominal segments bearing minute spines; 

 last abdominal segment terminated dorsally by a comparatively larger spine. 

 Dorsal body surface bearing several fine, short, erect hairs. Outer surfaces 

 of legs lightly browned. Ventral surface lemon yellow. Rostrum extending 

 to second pair of legs, lancets 1^2 to 2 times length of body. 



Second nymphal stage. Length 0.4 mm. to 0.55 mm. Width of head 

 between eye 0.18 mm. 



Yellowish, broadest across thorax. Somewhat similar to first stage except 

 that the dorsal brown markings are faint or absent ; anterior margin of head trun- 

 cate ; sides of thorax arcuate ; abdomen more elongate, s'des rounded and extrem- 



