BIOLOGICAL STUDIES ON THEEE APHIDIDiE. 165 



0.049 mm.; II, 0.049 mm.; Ill, 0.236 mm.; IV, 0.14T mm.; V, basal, 

 0.130 mm. ; filament, 0.244 mm. ; total, 0.855 mm. 



Pupa of winged olciparous female. — Head and thoracic segments 

 olive-yellow; abdomen pale yellow, with greenish tint. Eyes dark 

 red. Antenna? 5-segmented, all except last segment concoloroiis with 

 head. Antenna^ and head with bristles, as in other forms. Thorax 

 with several dark-green patches from which arise tnberculate bristles. 

 Legs, excepting tarsi, which are black, concolorous with body. 

 Wing-pads light brown. Abdomen Avith 8 longitudinal rows of 

 tnberculate spines, each spine with a basal patch of dark green. A 

 longitudinal row of small transverse dashes occurs on each side be- 

 tween the first and second rows of s^iines, counting from the median 

 line. Cornicles as in the other forms, and with dark-green basal 

 patches. Measurements: Length of body, 1.953 mm.; width, 0.863 

 mm.; antenna, I, 0.058 mm.; II, 0.048 mm.; Ill, 0.194 mm.; IV, 0.135 

 mm.; V, basal, 0.107 mm.; filament, 0.214 mm; total, 0.750 mm. 



Winded viviparous female. — Head and abdomen lemon-yellow, 

 with the thoracic segments brownish. Eyes red. Antenna^ with 

 several more or less noticeable hairs, much less conspicuous than in 

 the wingless pseudogyne ; all except the two basal segments and the 

 basal half of the third segment are dark ; a single circular sensorium 

 at ajDex of fourth segment and several at the apex of the basal portion 

 of the fifth segment. Beak hardly reaching to the coxa^ of the second 

 pair of legs. Plead and thorax with spinous tubercles much as in 

 the wingless pseudogyne. Legs concolorous with body, excepting 

 tips of tarsi, which are darkened. Stigma and cubitus pale yellow, 

 other wing-veins dusky. Abdomen with 8 longitudinal rows of 

 dark-green spots from which arise conspicuous tuberculate spines. 

 Between the first and second rows of spots from the median line, on 

 each side, is a row of small dark dashes. Cornicles tuberculiform, 

 and with dark-green basal patches. Style slightly constricted in the 

 middle. Measurements : Expanse of wings, 5.744-6.477 mm. ; length 

 of body, 1.641 mm. ; width, 0.734 mm. ; antenna, I, 0.065 mm. ; 

 II, 0.065 mm.; Ill, 0.277 mm.; IV, 0.196 mm.; V, basal, 0.147 mm.; 

 filament, 0.293 mm. ; total, 1.043 mm. ; style, 0.088 mm. 



OVIPAROUS GENERATION. 



Before first molt and 2J^-Ji8 hours old. male or female. — Color 

 sulphur-yellow. Head with a dark patch covering it almost entirely. 

 Eyes red. Antennae and legs transparent until a day old, graduall}^ 

 darkening until they become concolorous with the darker markings 

 of the body. Antenna? apparently only 4-segmented, a constriction 

 in the apical half of the third segment showing where this segment 

 later divides into two. At the distal end of the third segment is a 



