444 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 12 



black. During the fifth stage the nymphs wander about more freely 

 over the leaf and sometimes go to adjoining leaves. 



Description of Nymphal Stages 



First Stage. — Length, 0.5 mm.; greatest width, 0.15 mm. General shape an 

 elongate eUipse somewhat broader cephalad than caudad and more elongate than the 

 later stages. At first almost colorless but soon becoming dark brown. Beak 

 4-segmented and extending back to the sixth abdominal segment. Antenna 3-seg- 

 mented, the basal two segments being shorter than the third segment. The basal 

 segment is without spines or hairs, the second segment has a few short hairs, the third 

 segment has numerous long spines and hairs ; some with rounded tip and conical base, 

 others with pointed tip. Head with five prominent dorsal tubercles, two slightly 

 separated just above the base of the beak, each bearing a round-tipped spine; one 

 tubercle back of these on the median fine bearing two spines; two tubercles near the 

 posterior margin widely separated and each bearing two spines. Pro- and meso- 

 thorax have lateral tubercles with a spine on each and the mesothorax has a pair 

 of dorsal tubercles with one spine on each. Metathorax and first abdominal segment 

 are without spines. Legs armed with short pointed hairs and two bent sharp ter- 

 minal claws. There are nine abdominal segments visible above and each of these 

 excepting the first bears a tubercle surmounted by a round-tipped spine, on both 

 lateral margins of the segment. Two dorsal tubercles are on the second, fifth, sixth, 

 and eighth abdominal segments; those on the second and eighth bearing one round- 

 tipped spine each, and those on the fifth and sixth bearing two spines each. The 

 tenth abdominal segment may be seen from a lateral or ventral view and this segment 

 bears no spines or hairs. Minute awl-shaped spinules occur over the dorsal surface, 

 especially on the large tubercles of the fifth and sixth abdominal segments and on the 

 thorax. 



Second Stage. — Length, 0.68 mm.; greatest width, 0.27 mm. The bodj^ broader 

 in proportion to its length than in the first stage. Dark brown in color with numer- 

 ous minute spinules over the dorsal surface covering it much more completely than 

 before. Additional small spines have appeared on both dorsal and lateral tubercles 

 and the round-tipped spines present before have a slightly longer conical base now. 



Third Stage. — Length, 0.82 mm.; great-est width, 0.44 mm. The antenna has 

 four segments now. The round-tipped spines arise from a base longer than the 

 spines and a few small spines have appeared on the tubercles. The pro- and meso- 

 thorax are beginning to increase in prominence. 



Fourth Stage. — Length, 1.2 mm. ; greatest width, 0.7 mm. The -n-ing pads of the 

 mesothorax extend back over the metathorax and first abdominal segment at the 

 sides. The prothorax is more prominent than before. Bases of the round-tipped 

 spines are several times as long as the spines. A few new spines are present on the 

 lateral margins of the pro- and mesothorax and of the abdomen. The color is dark- 

 brown except in an irregular band across the abdomen just caudad of the wing pads 

 and on the lateral thirds of the prothorax where the color is yellowish. The minute 

 spinules cover the entire dorsum, being light colored on the yellowish portions and 

 dark on the brown portions. These spinules are also present on the bases of the 

 round-tipped spines. 



Fifth Stage. — Length, 1.6 mm.; greatest width, 0.96 mm. The wing pads now 

 extend back to the fourth abdominal segment at the sides and the prothorax is still 

 more prominent. A few more spines have appeared on the tubercles and many of 

 the sharp pointed spines have become round-tipped. Spines on the lateral margins 

 of those segments covered by the wing pads have disappeared. The yellowish parts 



